Chapter 1 Introduction
习题
3、(1) 5位; (2) 3位; (3) 2位; (4) 1位; (5) 2位. 4、RE?5
X?T0.1023?0.1024???0.001??0.1% T0.1024、
mol?L?1?J?K?1?mol?1?K?J?L?1?kg?m2?s?2?L?1?1000kg?m?1?s?2?1000Pa?kPa或
mol?L?1?J?K?1?mol?1?K?J?L?1?N?m?L?1?1000N?m?2?1000Pa?kPa
7、n?NaOH??m(NaOH)0.010kg??0.25mol
M(NaOH)40.0g?mol?11m(Ca2?)0.100kg?1?2n?Ca2?????5.00mol
?2?M(1Ca2?)1?40.0g?mol?1221m(Na2CO3)0.100kg?1?2n?Na2CO3????1.89mol
112??M(NaCO)?106g?mol?123228、n(ZnCl2)?m(ZnCl2)350g??2.57mol
M(ZnCl2)136.3g?mol?1此溶液的物质的量浓度为:
c(ZnCl2)?n(ZnCl2)2.57mol??3.48mol?L?1 V739.5mL此溶液的质量摩尔浓度为:
b(ZnCl2)?n(ZnCl2)2.57mol??3.95mol?kg?1
m(H2O)650gm(K?)20mgn(K?)M(K?)39.0g?mol?1????5.1mmol?L?1 9、c?K??VV100mLcCl???m(Cl?)366mgn(Cl?)M(Cl?)35.5g?mol?1????103mmol?L?1
VV100mL10、m(C6H12O6)?50.0g?L?1?500mL?25.0g
M(C6H12O6?H2O)198g?mol?1m(C6H12O6?H2O)?25.0g??25.0g??27.5g ?1M(C6H12O6)180g?mol
即称取27.5g C6H12O6·H2O晶体,溶于蒸馏水并稀释至500mL。
m(C6H12O6)25.0gn(C6H12O6)M(C6H12O6)180g?mol?1c(C6H12O6)????0.278mol?L?1
VV500mL
溶液中水的质量为:500mL?1.00kg?L?1?25.0g?475g,则葡萄糖的摩尔分数为:
m(C6H12O6)n(C6H12O6)M(C6H12O6)x(C6H12O6)??n(C6H12O6)?n(H2O)m(C6H12O6)m(H2O)?M(C6H12O6)M(H2O)25.0g180g?mol?1??0.0052525.0g475g??1180g?mol18.0g?mol?1
11、m?Na???5.0g
M(NaCl)58.5g?mol?1m?NaCl??5.0g??5.0g??13g ??1M(Na)23.0g?molV?NaCl??m(NaCl)13g??1.4L ?1?(NaCl)9.0g?L12、n?I2??
m(I2)0.508g?3??2.00?10mol ?1M(I2)254g?moln?KI?KMnO4??2n(I2)?2?2.00?10?3mol?4.00?10?3mol
Exercises
2.
29.837?29.24?0.018618?0.19
32.0654. Assume the volume of the solution is 1 L, thus the mass of the solution is:
m?1.024g?mL?1?1L?1024g
The mass of NH4Cl is: m(NH4Cl)?1024g?8.50%?87.0g The mass of solvent H2O is: m(H2O)?1024g?(1?8.50%)?937g
m?NH4Cl?87.0gn?NH4Cl?M?NH4Cl?53.5g?mol?11.63molb?NH4Cl??????1.74mol?kg?1
m(H2O)m(H2O)937g0.937kgx?NH4Cl??n?NH4Cl??n?NH4Cl??n(H2O)1.63mol1.63mol??0.0304m(H2O)937g1.63mol?1.63mol?18.0g?mol?1M(H2O)
c?NH4Cl??n?NH4Cl?1.63mol??1.63mol?L?1 V1L5. M(C3H8)?44g?mol?1; M(C4H10)?58g?mol?1
Assume the total moles of the sample is x, thus,
n(C3H8)?M(C3H8)?n(C4H10)?M(C4H10)?58g 0.43x?44g?mol?1?0.57x?58g?mol?1?58g
x?1.1mol
The mass of propane is: 0.43?1.1mol?44g?mol?1?21g; The mass of butane is: 58g?21g?37g 6. The mass of KAl(SO4)2 is:
M?KAl(SO4)2?258.2g?mol?1m?KAl(SO4)2???118.6mg??118.6mg?64.55mgM(KAl(SO4)2?12H2O)474.4g?mol?1m(KAl(SO4)2)64.55mgn(KAl(SO4)2)M(KAl(SO4)2)258.2g?mol?1c(KAl(SO4)2)????2.500?10?4mol?L?1VV1.000Lc(SO4)?2?c(KAl(SO4)2)?2?2.500?10?4mol?L?1?5.000?10?4mol?L?1
2?The density of the solution is 1.00 g?mL-1, thus the mass of the solution is 1.000 kg. Since the solution is very dilute, it can be considered that the mass of water(solvent) is approximately 1.000 kg,
m(KAl(SO4)2)64.55mgn(KAl(SO4)2)M(KAl(SO4)2)258.2g?mol?1b(KAl(SO4)2)????2.500?10?4mol?kg?1
m(H2O)m(H2O)1.000kg
Chapter 2 Colligative Properties of Solutions
习题
100g18.0g?mol?1??0.995100g10.0g??118.0g?mol342g?mol?11. x?HO?2P?P0x?H2O??2.34kPa?0.995?2.33kPa
2. (1)n甲,溶质?n乙,溶质?1.68g?3?4.91?10mol ?1342g?mol2.45g?3?3.55?10mol?n甲,溶质,溶剂的量相等 ?1690g?mol?x甲,H2O?x乙,H2O。相同温度下,乙溶液蒸汽压高。
(2)溶液乙中的溶剂可以转到甲溶液中。密闭容器中压强为P,则P甲溶液中凝结速率大于蒸发速率,溶质浓度降低;甲?P?P乙,乙溶液中蒸发速率大于凝结速率,浓度升高。直到两者浓度相等。
4.91?10?3mol3.55?10?3mol?(3),?mH2O?3.22g
20.00g?mH2O20.00g?mH2OmB3. ?Tb?KbbB?KbMBmAmBKb2.80g?512K?g?mol?1?MB???28g?mol?1
?TbmA0.51K?100g方法一:
?Tf?KfbB?KfmB2.80g?1.86?103K?g?mol?1?=1.9K?1MBmA28g?mol?100g方法二:
?Tb0.51K?1?Tf?KfbB?Kf?1.86K?kg?mol?=1.9K?1Kb0.512K?kg?mol?Tf?0?C??Tf?C??1.9?C
4. ?Tb?KbbB?KbmBMBmAmBKb0.538g?512K?g?mol?1?MB???162g?mol?1
?TbmA0.17K?10.0g设尼古丁的分子式为:?C5H7N?a
162g?mol?1a??2,分子式为:C10H14N2。 ?181g?mol5. ?Tb?KbbB?KbmBMBmAmBKb3.24g?5120K?g?mol?1?MB???256g?mol?1
?TbmA1.62K?40.0g设此单质硫的分子式为:sa
256g?mol?1a??8,分子式为:s8。 ?132g?mol6. 方法一:对于稀溶液,cB?bB
i. (1) (2) (4) 均为水溶液,其中(1) (2)为非电解质,浓度相等,凝固点下降值相等,凝固点(1)=(2);(4)相对于(1) (2)来讲,凝固点下降更多,则凝固点(1)=(2)> (4) ii. (3)为苯的溶液,纯苯的凝固点为5.5℃,
?Tf?Kf?C6H6?bB?5.12K?kg?mol?1?0.1mol?kg?1?0.512K,
则其凝固点大于0℃,为(1) (2) (3) (4)中的最高值。 排序:(3)> (1)=(2)> (4) 方法二:对于稀溶液,cB?bB
?1?1(1) ?Tf?Kf?H2O?bB?1.86K?kg?mol?0.1mol?kg?0.186K
0.1mol·L-1蔗糖水溶液的凝固点为:-0.186℃
?1?1(2) ?Tf?Kf?H2O?bB?1.86K?kg?mol?0.1mol?kg?0.186K
0.1mol·L-1甲醇水溶液的凝固点为:-0.186℃
?1?1(3) ?Tf?Kf?C6H6?bB?5.12K?kg?mol?0.1mol?kg?0.512K
0.1mol·L-1甲醇苯溶液的凝固点为:5.5℃-0.512℃=4.988℃
?1?1(4) ?Tf?iKf?H2O?bB?2?1.86K?kg?mol?0.1mol?kg?0.372K
0.1mol·L-1NaCl水溶液的凝固点为:-0.372℃ 排序:(3)> (1)=(2)> (4)
?17. (1) ??c?C6H12O6?RT?0.2mol?LRT
1?1?1??cNaCO?cNaCO?0.2mol?L?1?0.1mol?L?1 ?(2) 2323??2?2?2??ic?Na2CO3?RT?3?0.1mol?L?1RT?0.3mol?L?1RT 1?10.2?1?1?1??cNaPO?cNaPO??0.2mol?L?mol?L??(3) 34343?333???ic?Na3PO4?RT?4?0.20.8mol?L?1RT?mol?L?1RT 33?1?1(4) ??ic?NaCl?RT?2?0.2mol?LRT?0.4mol?LRT
排序:(4)> (2)> (3)> (1) 8. ib?NaCl???TfKf?0.26K?1?0.14mol?kg
1.86K?kg?mol?1?cos?NaCl??0.14mol?L?1?140mmol?L?1
(1)的说法正确。 9. ??cBRT?mBRT MBVmBRT2.00g?8.314J?mol?1?K?1?298K?MB???6.91?104g?mol?1
?V0.717kPa?0.100L10. bB?
?TfKf?0.52K?1?0.28mol?kg cos ? 0.28 mol·L-1 ?11.86K?kg?mol---
Π= cosRT = 0.28 mol·L1 ×8.314J·K1·mol1×310K= 720 kPa
11. 由题可知,两种溶液的质量摩尔浓度相等。b尿素?bB即:
m尿素mB?
M尿素mA,1MBmA,2?MB?mBM尿素mA,1m尿素mA,242.8g?60.05g?mol?1?200g??343g?mol?1
1.50g?1000g12. bB?0.020mol?2?0.010mol?3?0.040mol?30.19mol??1.9mol?kg?1
0.100kg0.100kg?Tb?KbbB?0.512K?kg?mol?1?1.9mol?kg?1?0.97K
Exercises
1. (calculating process omitted). (a): The boiling point (b.p.) is 102.72
?C, the freezing point (f.p.) is –9.89 ?C; (b): The b.p. is 101.97 ?C, the f.p. is –7.16 ?C. 2. ?Tf?5.50?2.36?3.14(K)
4.00g?5.10K?kg?mol?1MB???118g?mol?1
?TfmA3.14K?55.0g7.85g?5.10K?kg?mol?1??127g?mol?1 3. MB??TfmA1.05K?301gM(C5H4)?64g?mol?1?1?127g?mol?1 2mBKfmBKfTherefore, the molecular formula of this compound is C10H8. 4. The molality of the EG solution is:
mB651g?1bB???4.19mol?kg
MB?mA62.01g?mol?1?2505g?Tf?Kf?bB?1.86K?kg?mol?1?4.19mol?kg?1?7.79K
The freezing point of the solution is: (0?7.79)?C??7.79?C. (The calculation here has a relatively large error since the solution is not a dilute solution anymore.) 5. 10.0 mmHg corresponds to
??cBRT?10.0mmHg?101.3kPa?1.33kPa.
760mmHgnBmBmRTRT?RT?B VMBVMBVmBRT35.0g?8.314J?mol?1?K?1?298K?MB???6.52?104g?mol?1
?V1.33kPa?1L6. Assume the volume of the solution is 1 L, thus, The mass of NaCl is: 1.005g?mL?1?1L?0.86%?8.6g. The molarity of NaCl solution is:
cB?nBn8.6g?1?B??0.15mol?L, therefore, VMBV58.5g?mol?1?1L??icBRT?2?0.15mol?L?1?8.314J?mol?1?K?1?(273?37)K?7.7?102kPa
Chapter 3 Electrolyte solutions
习题
1、OH-、H2O、HCO3-、CO32-、NH3、NH2CH2COO-、HS-、S2-。 2、H3O+、NH4+、H2PO4-、NH3、[Al(H2O)6]3+、HCO3-、NH3+CH2COOH。
3、(1) 在H3PO4溶液中存在如下质子转移平衡:
H3PO4?H??H2PO4
?H2PO4?H??HPO4
?2?HPO42??H??PO4
3?H2O?H??OH?
?2?3??溶液中存在 H?,H2PO4.,HPO4.,PO4.和OH五种离子;离子浓3???,OH??。度由大到小的顺序是:?H????H2PO4?.???HPO42.????PO43?H3PO4不能完全电离,所以溶液中的H?浓度不是PO4.的三倍。
(2) NaHCO3是一种两性物质,在水溶液中存在下列质子转移平衡:
HCO3?H??CO3 HCO3?H2O?H2CO3?OH?
??2?HCO3-的酸离解常数和碱离解常数分别为:
KaHCO3??Ka2?H2CO3??5.6?10?11??KbHCO??3??K?CO?2?b23Kw1?10?14?8???2.3?10 Ka1?H2CO3?4.3?10?7由于Ka?HCO3???Kb?HCO3??,故HCO3-结合质子的能力大于其给出质子的能力,故此溶液显碱性。
NaH2PO4也是一种两性物质,在水溶液中存在下列质子转移平衡:H2PO4??H??HPO42?
H2PO4?H2O?H3PO4?OH?
?H2PO4-的酸离解常数和碱离解常数分别为:
?KaH2PO4?Ka2?H3PO4??6.2?10?8
??KbH2PO??4??K?PO?b33?4KW1.0?10?14?12???1.3?10 ?3Ka17.5?10由于Ka?H2PO4???Kb?H2PO4??,故H2PO4-给出质子的能力大于其结合质子的能力,故此溶液显酸性。 4、盐效应、同离子效应。
5、(1)和(2):溶解度降低(同离子效应); (3):溶解度稍有增大(盐效应); (4):溶解度大大增大(形成配离子)。
6、在H2S溶液中存在如下质子转移平衡:
H2S?H2O?HS??H3O?
HS??H2O?S2??H3O?
Ka1?8.91?10-8,Ka2?1.12?10-13
Ka1?ca?8.9?10?9?20Kw,Ka1/Ka2?100ca0.106??1.1?10?500?8Ka18.91?10
第二步解离生成的H+和HS-的解离可忽略,因此,
[H?]?Ka1?ca=8.91?10-8?0.10?9.4?10?5(mol?L?1) [HS?]?[H?]?9.4?10?5(mol?L?1)
Ka2[H?][S2?]2??13?1? [S]?K?1.1?10(mol?L) a?[HS]2Kb1?cb?7.9?10?7?0.015?20Kw7、cbKb1?0.015?500?77.9?10
[OH?]?Kb1?cb=7.9?10-7?0.015?1.1?10?4(mol?L?1) pOH??log(1.1?10?4)?3.96
pH?14.00?pOH?14.00?3.96?10.04
8、在C7H6O3溶液中存在如下质子转移平衡:
C7H6O3?H2O?C7H5O3?H3O?
?C7H5O3?H2O?C7H4O3?2??H3O?
Ka1?1.06?10-3,Ka2?3.6?10-14 Ka1?ca?20Kw,Ka1/Ka2?100,ca?500 Ka1第二步解离生成的H+和C7H5O3-的解离可忽略,设第一步解离的解离度为?, 则有:
Ka10.065?2c?2?3?,1.06?10?,解得:??0.12
1??1??[H?]?0.065?0.12?7.8?10?3(mol?L?1)
pH??log(7.8?10?3)?2.11
[C7H5O3]?[H?]?7.8?10?3(mol?L?1)
?
[C7H4O3]?Ka2?3.6?10?14(mol?L?1)
2?9、(1) 质子转移平衡常数为:
[H?][NO2]?Ka(HNO2)4.6?10?4[HCN][NO2][HNO2]5K?????9.4?10??1
Ka(HCN)4.9?10?10[HNO2][CN?][H?][CN?][HCN]?反应偏向右方。
(2) 质子转移平衡常数为:
[H?][SO4]Ka(HSO4)1.2?10?2K?????26?1 ????4?[HSO4][NO2][H][NO2]Ka(HNO2)4.6?10[HNO2][HNO2][SO4][HSO4]2???2?反应偏向右方。
(3) 质子转移平衡常数为:
[H?][NH3]Ka(NH4)Kw[NH4]K????????K(HAc)Ka(HAc)?Kb(NH3)[NH4][Ac][H][Ac]a
[HAc]1.0?10?14?5??3.1?10??1?5?51.8?10?1.8?10[HAc][NH3]??反应偏向左方。
(4) 质子转移平衡常数为:
1.0?10?14?13K?????8.3?10??1 2?2???2?[SO4][H2O][H][SO4]Ka(HSO4)1.2?10Kw[HSO4]?[HSO4][OH?]?[H?][OH?][H2O]反应偏向左方。
10、NaN3溶于水后完全解离成Na+和N3-:
NaN3?N3?Na?
?c(NaN3)?0.010mol?L-1--1 c(Na)?c(N)?0.010mol?L3?溶液中存在如下质子转移平衡,溶液中[H+]主要由N3-决定:
N3?H2O?HN3?OH?
KW1.00?10-14Kb?==5.3?10-10 -5Ka(HN3)1.9?10?由于 c?Kb?0.01?5.3?10-10c0.0120Kw,?Kb5.3?10-10500
所以 [OH?]?[HN3]?Kb?c?5.3?10-10?0.01mol?L?1?2.3?10-6mol?L?1
KW1.00?10-14-9?=4.3?10得出 [H3O]? [OH?]2.3?10-6?11、⑴ 溶液中存在反应:
H3PO4+2NaOH?Na2HPO4?2H2O
1L?0.01mol1000mL
1Ln(NaOH)?c?V?0.20mol?L-1?100mL??0.02mol1000mLn(H3PO4)?c?V?0.10mol?L-1?100mL?c(HPO4)?0.05mol?L?1
2?Na2HPO4在水溶液中,HPO4-作为两性负离子,发生质子传递反应为:
2?3?作为酸 HPO4?H2O?PO4?H3O?
作为碱 HPO42??H2O?H2PO4??OH? 附录三(p290):
Ka1(H3PO4)?6.9?10-3,pKa1?2.16Ka2(H3PO4)?6.1?10-8,pKa2?7.21Ka3(H3PO4)?4.8?10-13,pKa3?12.32因为:
Ka3?c?4.8?10-13?0.05?2.4?10-1420Kw,c?0.0520Ka2所以溶液中,水的自电离所产生的H+不能忽略:
Ka2(Ka3?c?Kw)Ka2(Ka3?c?Kw)[H]??Ka2?cc?6.1?10-8?(2.4?10-14?1.00?10-14)??2.0?10-10 0.05pH??lg[H?]??lg2.0?10-10?9.70⑵ 溶液中存在反应:
Na3PO4+2HCl?NaH2PO4?2NaCl
c(H2PO4-)?0.05mol?L-1
NaH2PO4在水溶液中,H2PO4-作为两性负离子,发生质子传递反应为: 作为酸H2PO4??H2O?作为碱H2PO4?H2OHPO43??H3O?
H3PO4?HO-
因为:
Ka2?c?6.1?10-8?0.05?3.0?10-9所以溶液的pH为:
20Kw,c?0.0520Ka111pH?(pKa1?pKa2)?(2.16?7.21)?4.68
2212、AgCl开始沉淀时,Ag+的浓度为
[Ag]??Ksp(AgCl)[Cl?]1.77?10?10??1.8?10?8(mol?L?1)
0.010Ag2CrO4开始沉淀时,Ag+的浓度为
[Ag]??Ksp(Ag2CrO4)[CrO4]2?1.12?10?12??1.1?10?5(mol?L?1)
0.010当在Cl-和CrO42-的混合溶液中逐步加入AgNO3时,Cl-在较低的Ag+浓度下首先达到其溶度积,即Cl-首先沉淀出来。随着Ag+的逐步加入,溶液中Cl-浓度逐渐降低,Ag+浓度逐渐增大,当Ag+增大到CrO42-达到其溶度积时,Ag2CrO4开始沉淀出来,此时,
[Ag?]?1.1?10?5mol?L?1,则有:
[Cl]??Ksp(AgCl)[Ag?]1.77?10?10?5?1??1.6?10(mol?L) ?51.1?1013、略
?14、[C3H5O3]?[H?]?10?2.45
[C3H5O3][H?]10?2.45?10?2.45?4Ka?, 1.4?10?
[HC3H5O3][HC3H5O3]?[HC3H5O3]?9.0?10?2(mol?L?1)
c(HC3H5O3)?[HC3H5O3]?[C3H5O3]?9.0?10?2?10?2.45?9.4?10?2(mol?L?1) 10?1.415、?5.0?103.6?4.0?103
10?16、由题目可知,BHX为弱酸弱碱溶液,其水溶液中存在的主要成分是B、HX和H2O,具有下列反应:
HX?H2OB?H2OX??H3O?,BH??HO-,Kb(B)?1.0?10-3H3O?(aq)?HO-(aq)
H2O(l)?H2O(l)B与HX之间还能发生酸碱反应
B(aq)?HX(aq)BH?(aq)?X-(aq)
作为两性溶液,溶液的pH为:
pH?12(pKa(HX)?pKa(B)),?pKa(HX)?2pH?pKa(B)?2pH?(14.00?pKb(B))因 pK
b(B)??lgKb(B)??lg1.0?10-3?3.00? pKa(HX)=2?8.00?(14.00?3.00)?5.00即HX的Ka为:
K?5a(HX)?10?1.00?10-5
17、(1) 0.20mol·L-1的HCl溶液pH=0.70,pH值增大到4.0,则需要
降低H+的浓度,应加入碱性NaAc。 (2) NaAc过量,发生以下反应,
HCl+NaAcHAc+NaCl
溶液中HAc和NaAc的浓度为:
?HAc??0.20mol?L?1c?V2V?0.10mol?L?1
?NaAc??2.0mol?L?1?V?0.20mol?L?1c?V2V?0.90mol?L?1
K?HAc??[H?][Ac?][H?]c??[HAc]?NaAc?acHAc??9[H?]??Ka?HAc?1.8?10?5?[H]9?9?2.0?10?6
pH?5.70
(3) NaOH过量,发生以下反应,
HCl+NaOHH2O+NaCl
2.0mol?L?1?V?0.20mol?L?1?V?0.90mol?L?1 溶液中c?NaOH??2VpH?14.00?pOH?14.00?log[OH?]?14.00?log(0.90)?13.95
17、由题目可知:
c(HCl)?0.20mol?L-1
HCl作为强电解质,在水中完全解离:
pH??lg[H?]??lg0.20?0.70
⑴要使pH=4.0,需要加入NaAc
⑵加入等体积的2.0mol﹒L-1NaAc后,溶液中存在反应:
NaAc+HCl?HAc?NaCl
2.0mol?L-1?V?1.0mol?L-1, 反应前 c(NaAc)?2V0.20mol?L-1?V?0.10mol?L-1 c(HCl)?2V-1c(HAc)?c(HCl)?0.10mol?L反应后
-1 c(NaAc)?0.90mol?L
此时,溶液中主要成分为HAc、Ac-和H2O,具有下列酸碱反应:
HAc?H2OAc??H3O?
初始浓度 c(HAc) c(NaAc) 反应中消耗 c’ c’ 平衡浓度 c(HAc)-c’ c(NaAc)+c’
依据同离子效应,因原溶液中存在Ac-而使得该反应解离c’非常微弱,
可忽略不计。平衡浓度即可近似为初始浓度,反应达到平衡时:
Ka(HAc)[Ac?][H3O?][Ac?][H3O?]0.90mol?L-1[H3O?]???[HAc][HAc]0.10mol?L-10.10mol?L-1Ka(HAc)-1-50.10mol?L?1.75?10-6?[H3O?]???1.9?10 0.90mol?L-10.90mol?L-1pH??lg[H?]??lg1.9?10-6?5.72⑶加入等体积的2.0mol﹒L-1NaOH后,溶液中存在反应:
HCl+NaOH?NaCl?H2O
-1-1?L?V2.0mol-12.0)molc(NaOH??L?V?1.0mol-1?L 反应前 c(NaOH)? 2V?1.0mol?L?2V 0.20mol?L-1?V-1c(HCl)??0.10mol?L2V反应后,溶液主要成分为NaOH:
c(NaOH)?0.90mol?L-1pOH??lg[OH?]??lg0.90?0.046pH?14.00?pOH?14.00?0.046?13.9518、c?1g?3?1?1.6?10mol?L
324.4g?mol?1?1.90L
Kb1?10?5.1?7.9?10?6??Kb2,第二步解离可忽略。 c?Kb1?1.6?10?3?7.9?10?6?20Kw c/Kb1?1.6?10?3/7.9?10?6?500 Kb1?321.6?10??c?2????0.068 , 7.9?10?6?1??1??[OH?]?c???1.6?10?3?0.068?1.1?10?4(mol?L?1) pOH??log[OH?]??log(1.1?10?4)?3.96
pH?14.00?pOH?14.00?3.96?10.04
19、尿液中Ca2+浓度为:
m(Ca2?)0.10gM(Ca2?)40g?mol?12?c(Ca)???1.8?10?3mol?L?1
V1.4L在Ca3(PO4)2溶液中,存在其沉淀-溶解平衡:
Ca3(PO4)2(s)?3Ca2?(aq)?2PO4(aq) Ksp(Ca3(PO4)2)?[Ca2?]3[PO4]2
3?3?依据溶度积规则,当Ip≤Ksp时,溶液中不会有沉淀生成: 即此时
c(PO4)?[PO4]?3?3?Ksp(Ca3(PO4)2)[Ca]2?3??2.07?10?33?13?1?6.0?10(mol?L) ?33(1.8?10)20、⑴
血液中,c(Fe3?)?5.0?10-5mol?L?1
在Fe(OH)3的饱和溶液中,存在沉淀-溶解平衡:
Fe(OH)3(s)Fe3?(aq)?3OH?(aq)Ksp{Fe(OH)3}?[Fe3?][OH?]3
依据溶度积规则,要使99t3?沉淀,则Ip{Fe(OH)3}Ksp{Fe(OH)3}, 且溶液中仅剩余1t3?:[Fe3?]?1%?c(Fe3?)?5.0?10-7mol?L?1
c(OH?)[OH?]?3Ksp{Fe(OH)3}[Fe3?]-392.8?10-11?1?3?1.8?10mol?L5.0?10-7
pOH??lg[OH?]??lg1.8?10-11?10.74人体37℃时,pKw=13.685
pH?pKw?pOH?13.685?10.74?2.94 ⑵ 在pH=7.40的血液中,
pOH?pKw?pH?13.685?7.40?6.28[OH?]?10?6.28?5.2?10-7mol?L?1此时,溶液中 [Fe]?3?
Ksp{Fe(OH)3}[OH?]32.8?10-39-20?1??2.0?10mol?L -73(5.2?10)即溶液中[Fe3?]含量非常少,多数以结合形式稳定存在。
21、(1) 混合后HCl与NH3恰好完全反应
NH3+HClcNHNH4Cl
??4?0.10mol?L?1?V??0.050mol?L?1
2VKaNH??4?Kw1.0?10?14?10???5.6?10 ?5Kb?NH3?1.8?10cKa?0.050?5.6?10?10?2.8?10?11?20Kw,c/Ka?500按最简式计算: [H?]?cKa?2.8?10?11?5.3?10?6, pH?5.28.
(2) 混合后HAc与NH3恰好完全反应,生成的NH4Ac为两性物质。
NH3+HAcNH4Ac
0.10mol?L?1?Vc?NH4Ac???0.050mol?L?1
2V?cKa?20Kw,c?20Ka,
1.0?10?14?5?7?1[H]?KaNHKa?HAc???1.8?10?1.0?10mol?L ?51.8?10???4?pH=7.00
(3) 混合后HCl与Na2CO3恰好完全反应,生成的NaHCO3为两性物质。
Na2CO3+HClNaHCO3
0.10mol?L?1?Vc?NaHCO3???0.050mol?L?1
2VcKa2?20Kw,c?20Ka1, pH?1?pKa1?pKa2??1?6.37?10.25??8.31 2222、⑴
0.20mol?L-1H3PO4和0.20mol?L-1Na3PO4等体积混合,溶液存在反应:
H3PO4+Na3PO4?NaH2PO4?Na2HPO4
因为c(H3PO4)?c(Na3PO4)?0.10mol?L 所以c(NaH2PO4)?c(Na2HPO4)?0.10mol?L-1
H2PO4?和HPO42?作为共轭酸碱对,溶液中存在酸碱反应平衡:
-1H2PO4??H2OHPO42??H3O?
因同离子效应,H2PO4?解离离子可忽略不计:
2??[HPO][HO]?43K(HPO)?即 a224
[H2PO4?]Ka2(H2PO4?)[H2PO4?]6.1?10-8?0.10mol?L-1?[H3O]???6.1?10-8 2?-1[HPO4]0.10mol?L?pH??lg[H?]??lg6.1?10-8?7.21
⑵
0.20mol?L-1Na2CO3和0.10mol?L-1HCl等体积混合,溶液存在反应:
Na2CO3?HCl?NaHCO3?NaCl
溶液中主要成分是0.05mol?L-1Na2CO3、0.05mol?L-1NaHCO3和H2O,因为
HCO3?和CO32?作为共轭酸碱对,溶液中存在酸碱反应平衡:
HCO3??H2OCO32??H3O?
因同离子效应,HCO3?解离离子可忽略不计:
[CO32?][H3O?]Ka2(HCO3?)[HCO3?]??Ka2(HCO3)??[HO]??K(HCO3a23)?2?[HCO3][CO3]
?pH?pKa2(HCO3?)?10.3323、PbI2饱和溶液中的Pb2+浓度为:
[Pb]=32?Ksp?PbI2?4?99.8?10?3?1.3?10?3mol?L?1
4PbSO4饱和溶液中的Pb2+浓度为:
[Pb2?]=Ksp?PbSO4??2.53?10?8?1.59?10?4mol?L?1
计算结果表明,虽然两者的容度积相近,但是两者的溶解度相差较大,饱和溶液中的Pb2+浓度也不相同。 24、Mn(OH)2饱和溶液中存在如下平衡:
Mn(OH)2(s)Mn2+(aq)+2OH-(aq)
(1) Mn(OH)2的溶解度:
S=3Ksp?Mn?OH?2?4?132.06?10?3?3.72?10?5mol?L?1
4(2) [Mn2?]?S?3.72?10?5mol?L?1[OH?]?2S?2?3.72?10?5mol?L?1?7.44?10?5mol?L?1
2.06?10?13??2.1?10?11mol?L?1 (3) S?[Mn]=?22[OH]0.102?Ksp11?S?[OH]=(4)
22?Mn?2?Ksp12.06?10?13??5.0?10?7mol?L?1 20.2025、(1)反应前,n?H3PO4??0.10mol?L?1?1.0L?0.10mol
n?NaOH??6g?0.15mol,则恰好进行如下反应: ?140g?mol2H3PO4+3NaOHNa2HPO4+NaH2PO4+3H2O
0.10mol 0.15mol 0.050mol 0.050mol 反应后:c?Na2HPO4??c?NaH2PO4??Ka22?4??240.050mol?0.050mol?L?1 1.0L??8?HPO??H?c?NaHPO??H?????H??6.2?10?HPO?c?NaHPO?2?424mol?L?1, pH?7.21
(2) 37℃时溶液的渗透压力为:
2????cHPO4?cH2PO4?cNa?RT??????????6.0g?1?1??0.050mol?L?1?0.050mol?L?1??8.314J?K?mol?310K ??140g?mol?1.0L???644KPa(3) 加入葡萄糖后,溶液的渗透浓度为:
2??cos?cHPO4?cH2PO4?cNa??c?C6H12O6?????1???6.0g18g ?0.050mol?L?0.050mol?L???140g?mol?1.0L180g?mol?1?1.0L
?1 ?0.35mol?L?1?350mmol?L?1?300mmol?L?1 此溶液为高渗溶液。
26、⑴
500mLc(MgCl2)?0.20mol?L-1和500mLc(NH3?H2O)?0.20mol?L-1混合,溶液
中存在难溶强电解质的沉淀-溶解平衡:
Mg2?(aq)?2OH?(aq)Mg(OH)2(s)
Ksp(Mg(OH)2)?[Mg2?][OH?]2
强电解质MgCl2水中完全解离 c(Mg2?)?0.10mol?L-1 而溶液的OH-主要取决于一元弱碱NH3?H2O:
c?Kb(NH3)?0.10?1.8?10-5c0.1020Kw,?Kb(NH3)1.8?10-5500
[OH?]?Kb(NH3)?c?1.8?10-5?0.10mol?L?1?1.3?10-3mol?L?1依据溶度积规则:
Ip(Mg(OH)2)?c(Mg2?)c(OH?)2?0.10?(1.3?10-3)2?1.7?10-7
而Ksp(Mg(OH)2)?5.61?10-12 即Ip(Mg(OH)2)Ksp(Mg(OH)2) 所以,混合后溶液有沉淀生成。
⑵ 依据溶度积规则,当Ip(Mg(OH)2)?Ksp(Mg(OH)2)时,溶液应无沉淀:
c(Mg2?)?0.10mol?L-1c(OH)?[OH]???Ksp(Mg(OH)2)[Mg2?] 5.61?10-12-6-1??7.5?10mol?L0.10Kw1.00?10?14即[H3O]??=1.3?10?9 ??6[OH]7.5?10?因溶液中存在NH3-NH4+的酸碱平衡:
NH3?H2ONH4??OH?K(NH3)[NH3] [NH4?][OH?]Kb(NH3)??[OH?]?b[NH3][NH4?]Kb(NH3)[NH3]1.8?10?5?0.10[NH4]?==0.24mol?L ??6[OH]7.5?10?因溶液总体积为1L,即
m(NH4Cl)?n(NH4Cl)?Mr(NH4Cl)
?n(NH4?)?Mr(NH4Cl)?0.24mol?53.5g?mol?1?13g
Exercises
1. The final concentration of HPr is:
c(HPr)?125.0mL?0.40mol?L?1?0.10mol?L?1, therefore,
500.0mLc?Ka?0.10?1.34?10?5?1.34?10?6??20Kw and c0.10??500, then ?5Ka1.34?10[H?]?c?Ka?1.34?10?6?1.16?10?3(mol?L?1)
pH??log[H?]??log(1.16?10?3)?2.94
2. The dessociation reaction (or hydrolysis) of ethylamine is: CH3CH2NH2 + H2O ? CH3CH2NH3+ + OH-
Assume ethylamine is a weak base and most of OH- is resulted from the hydrolysis of ethylamine, then,
[CH3CH2NH2]?0.10(mol?L?1), and
Kw1.00?10?14?3?1[CH3CH2NH3]?[OH]???7.2?10(mol?L) ??11.86[H]10??[CH3CH2NH2][OH?](7.2?10?3)2Kb(CH3CH2NH2)???5.2?10?4
[CH3CH2NH2]0.10Kw1.0?10?14?11Ka(CH3CH2NH3)???1.9?10
Kb(CH3CH2NH2)5.2?10?4?3. Assume HP = pivaic acid, the pH of a 0.100 mol·L-1 HP solution is 3.0, thus,
[H?][P?](10?3.0)2Ka(HP)???10?5.0
[HP]0.100Kw10?14.0Kb(P)???5.0?10?9.0
Ka(HP)10?In the 0.100 mol·L-1 NaP solution, [P?]?0.100, [HP]?[OH?]
[HP][OH?][OH?]2Kb(P)???10?9.0, thus ?0.100[P]??[OH?]?10?5.0
pH?14.0?pOH?14.0?log[OH?]?14.0?log(10?5.0)?9.0
[H?][A?](0.086?3.2%)2??9.1?10?5 4. (1) Ka?[HA]0.086(1?3.2%)
(2) [H?]?10?2.48?3.3?10?3
[H?][A?][H?]2Ka(HA)??
[HA][HA][H?]2(3.3?10?3)2?1c(HA)?[HA]???0.12(mol?L) ?5Ka(HA)9.1?105. (1) S1(SrSO4)?Ksp(SrSO4)?3.44?10?7?5.87?10?4(mol?L?1)
(2) S2(SrSO4)?Ksp(SrSO4)[SO4]2?3.44?10?7??3.44?10?6(mol?L?1)
0.10006. Ca3(PO4)2?3Ca2?(aq)?2PO43?(aq)
[PO4]?3.3?10?7(mol?L?1)
3[Ca2?]??3.3?10?7?5.0?10?7(mol?L?1)
2Ksp[Ca3(PO4)2]?[Ca2?]3[PO4]2?(5.0?10?7)3(3.3?10?7)2?1.4?10?32
3?3?2?7. Ksp(PbSO4)?[Pb2?][SO4]
Ksp(Ag2SO4)?[Ag?]2[SO4]
2?(1) When PbSO4 precipitates,
[SO4]?2?Ksp(PbSO4)[Pb2?]2.53?10?8??1.7?10?7
0.15When Ag2SO4 precipitates,
[SO4]?2?Ksp(PbSO4)[Ag?]21.20?10?5?4??3.0?10
0.202PbSO4 will precipitate first.
(2) when Ag2SO4 starts to precipitates, [SO42?]?3.0?10?4
?[Pb]?2?Ksp(PbSO4)[SO4]2?2.53?10?8?5??8.4?10 3.0?10?48.4?10?5?100%?0.056%Pb2+ remains in the solution. or only
0.15
Chapter 4 Buffer solutions
习题
3、(1)、(2)、(4)、(5)
4、吡啶过量,混合后体系为弱碱吡啶和弱酸吡啶盐酸盐的混合物,
是缓冲溶液。吡啶的pKb为8.77,则吡啶盐酸盐的pKa为14.00-8.77=5.23。
pH?pKa?lg[C5H5N]0.3?0.1?5.23?lg?5.53 ?0.1[C5H6N]10.0g106g?mol?12?2??0.377mol?L?1 5、[CO3]?c(CO3)?250mL10.0g84.0g?mol?1??[HCO3]?c(HCO3)??0.476mol?L?1
250mL此缓冲溶液的pH为:
[CO32?]0.377pH?pKa?lg?10.33?lg?10.23
[HCO3?]0.4766、设溶液中甲酸的物质的量浓度为x mol?L-1,则甲酸钠的物质的量
浓度为(0.400-x) mol?L-1,由题意得:
3.90?3.75?lg0.400?x 解得,甲酸浓度为x = 0.166 mol?L-1;甲酸钠浓x?1度为0.400?x?0.400?0.166?0.234(mol?L)。
200mg40.0g?mol?17、加入的NaOH物质的量浓度为:?0.0500mol?L?1,
100mL
设原缓冲溶液中[HB] = x mol?L-1,则[B-] = (0.25 – x) mol?L-1;加入NaOH后,[HB] = (x –0.0500) mol?L-1,则[B-] = (0.30 – x) mol?L-1,则有:
5.60?5.30?lg原
缓
0.30?x?1,解得,x?0.133(mol?L)
x?0.0500溶
液
的
pH
值
为
:
冲
pH?5.30?lg0.25?x0.25?0.133?5.30?lg?5.24 x0.1338、Aspirin的总的物质的量为: nAsp?nAspH??0.65g?0.0036mol180.2g?mol?1能从胃中吸收的Aspirin是游离酸的形式,设其物质的量为 x,则有: pH?pKa?lgnAsp?nAspH?3.48?lg0.0036mol?xx病人服用解酸药后,胃溶物的pH为2.95,则有: 2.95?3.48?lg0.0036mol?xx? x = 0.0028 mol
病人可以从胃中立即吸收的Aspirin为: 0.0028 mol ? 180.2 g·mol-1 =
0.50 g 9、混合后[Ac?]?
0.10?1?0.025mol?L?1, 3?1[HAc]?0.10?(3?1)?0.050mol?L?1
3?1
[Ac?]0.025?4.75?lg?4.45 缓冲溶液的pH值为:pH?pKa?lg[HAc]0.050缓冲容量为:
0.025mol?L?1?0.050mol?L?1[Ac?][HAc]?1??2.303??2.303??0.038mol?L ??1?1[Ac]?[HAc]0.025mol?L?0.050mol?L10、n(H2Bar)?18.4g?0.100mol ?1184g?moln(NaOH)?6.00mol?L?1?4.17mL?0.0250mol
[H2Bar]?[HBar?]?0.100?0.0250mol?0.075mol?L?1
1000mL0.0250mol?0.0250mol?L?1
1000mL[HBar?]0.0250pH?pKa1?lg?7.43?lg?6.95
[H2Bar]0.075[H2Bar][HBar?]0.025mol?L?1?0.075mol?L?1?1??2.303??2.303??0.043mol?L[H2Bar]?[HBar?]0.025mol?L?1?0.075mol?L?111、参见教材习题答案(p301)。
12、 (1) NaOH为强碱,因此需加入HCl溶液50 mL。
(2) 设需加入HCl溶液 x mL, 则有:
7.00?9.25?lg50?x,解得,x?49.7mL x(3) 设需加入HCl溶液 x mL, 则有:
7.00?7.21?lg50?x, 解得,x?31mL x 溶液(3)有较好的缓冲能力,溶液(2)有极弱的缓冲能力,
溶液(1)没有缓冲能力。 13、需要NH4Cl的量为:
0.125mol?L?1?1L?53.5g?mol?1?0.125mol?53.5g?mol?1?6.69g
设需要NaOH的物质的量为 x mol,则有:
9.00?9.25?lgx,解得,x?0.045mol
0.125?x0.045mol?45mL
1.00mol?L?1 则需要1.00 mol?L-1 NaOH溶液的体积为:
14、设需要H3PO4溶液 x mL,则NaOH溶液的体积为 (100-x) mL。
缓冲溶液的pH为7.40,因此缓冲体系为H2PO4-?HPO42-。加入的
NaOH 首先全部把H3PO4转化为H2PO4-,然后把部分H2PO4-转化为HPO42-形成缓冲体系。根据此计量关系,溶液中缓冲体系的浓度为:
[HPO42?(100?x?x)mL?0.020mol?L?1]??(100?2x)?2.0?10?4mol?L?1
100mL[x?(100?2x)]mL?0.020mol?L?1[H2PO4]??(3x?100)?2.0?10?4mol?L?1
100mL?由pH?pKa?lg
[HPO4][H2PO4]?2?得,
(100?2x)?2.0?10?47.40?7.21?lg,解得,x?38.3mL
(3x?100)?2.0?10?4需要H3PO4和NaOH溶液各38.3 mL和61.7 mL。
15、⑴设加入的HCl的物质的量为 x mol,则有:
7.40?7.85?lg0.0500?0.100?x,解得,x?0.0024mol
0.0500?0.100?x0.0024mol?48mL ?10.0500mol?L需要HCl溶液的体积为:
⑵ 溶液中存在Tris?Tris?HCl,c(Tris)?c(Tris?HCl)?0.050mol?L?1 等渗溶液cos= 280 ? 320 mmol · L-1,设加入的NaCl的物质的量为 x
mol:
n(总)?n(Tris)?n(Tris?HCl)?in(NaCl)?280mmol?L?1?Vc(Tris)?c(Tris?HCl)?ic(NaCl)?280mmol?L?c(NaCl)?0.090mol?L?1m(NaCl)?c(NaCl)V?Mr?0.090mol?L?0.148L?58.5g?mol?0.78g[HCO3]24.0?90%pH?pK'?lg?6.10?lg?7.36?7.35 16、a[CO2]1.20??1
?1?1
不会引起酸中毒。
Exercises
5. The total moles of buffer component is: n?0.150mol?L?1?500mL?0.0750mol
Assume the needed amount-of-substance of concentrated acetic acid is
x mol, therefore,
5.00?4.76?lg0.0750?x, solve the equation, you get x?0.0274mol xThe mass of sodium acetate is:
(0.0750?0.0274)mol?136.1g?mol?1?6.48g
The volume of concentrated acetic acid is:
0.0274mol?1.57mL ?117.45mol?L6. According to Henderson-Hassenbalch equationpH?pKa2'?lg
[HPO4][H2PO4]??2?
7.40?6.80?lg[HPO4][H2PO4]?2?, solve the equation, you get
[H2PO4][HPO4]2??0.25
Chapter 5 Colloid solutions
习题
1、略。
2、20 ?C时水的?值为0.728 N?m-1, 由此可知20 ?C时水的比表面自
由能为0.728 J?m-2。把半径为1.00 mm的水滴分散为半径为1.00?10-3 mm
4?(1.00mm)33的小水滴后,小水滴的数目为:
4?(1.00?10?3mm)33?109
水滴表面积的增长为:
4?(1.00?10?3mm)2?109?4?(1.00mm)2?1.26?104mm2?1.26?10?2m2
分散水滴所作的功为:1.26?10?2m2?0.728J?m?2?9.17?10?3J
3、4、5、6、略
7、溶液混合时Cl-的物质的量为:0.02mol?L?1?12mL?2?10?4mol
Ag+的物质的量为:0.05mol?L?1?100mL?5?10?3mol
Ag+过量,制备的AgCl溶胶胶粒因吸附Ag+而带正电,溶胶胶团式为:
[(AgCl)m?nAg??(n?x)NO3]x?xNO3
???8、AgNO3溶液过量时胶粒带正电荷。电解质的聚沉能力顺序为:
[Fe(CN)6]3->SO42->Cl-, 即:K3[Fe(CN)6]>MgSO4>AlCl3 KI溶液过量时胶粒带负电荷。电解质的聚沉能力顺序为:
Al3+>Mg2+>K+, 即:AlCl3>MgSO4> K3[F e(CN)6]
25mL?0.016mol?L?1?80mL,9、即要加入少于80mL的AgNO3溶液。 ?10.005mol?L10?17题、略。
Chapter 6 Rreaction heat, direction and extent of chemical reactions
习题
2、(1) ?U = Q + W = -2.5 kJ – 500 J = -3.0 kJ (2) ?U = Q + W = -650 J + 350 J = -300 J 4、(1) ?rHm????rHm?,1?40kJ?mol?1
(2) ?rHm??2??rHm??,1?80kJ?mol?1
(3) ?rHm???rHm?,1??rHm?,2?20kJ?mol?1
6、?rHm?,298.15: 298.15K下化学反应的标准摩尔焓变。
?fHm(H2O,g): 气态水的标准摩尔生成焓。
??cHm(H2,g): 氢气的标准摩尔燃烧焓。 Sm?,298.15?(H2,g): 298.15K下氢气的标准摩尔熵。
?rSm?,T: 温度T下化学反应的标准摩尔熵变。
: 温度T下化学反应的标准摩尔吉布斯自由能变。
?rGm?,T?fGm(CO2,g): CO2气体的标准摩尔生成吉布斯自由能。
?K?: 化学反应的标准平衡常数。
7、(1) - (2) ? 6 - (3) ? 3, 得:
C6H6(l)?6C(gra)?3H2(g)
?rHm??49.2kJ?mol?1
?因此反应6C(gra)?3H2(g)?C6H6(l)的?rHm??49.2kJ?mol?1 8、2N2H4(l)?N2O4(g)?3N2(g)?4H2O(l)
?rHm?3?fHm(N2,g)?4?fHm(H2O,l)?2?fHm(N2H4,l)??fHm(N2O4,g)?3?0?4?(?285.8kJ?mol?1)?2?50.63kJ?mol?1?9.16kJ?mol?1??1253.6kJ?mol?1?????9、(1) ? 3 - (2) - (3) ? 2, 得:6Fe(s)?6CO2(g)?6FeO(s)?6CO(g) 则有:?rHm?rGm??,4?3??rHm?,1??rHm6?,2?,2?2??rHm?,3??11.0kJ?mol?1
,4?3??rGm?,1??rGm6?,4?2??rGm?,3??6.2kJ?mol?1
?rSm?,4??rGm?,4??rHmT??16.1J?K?1?mol?1
10、(1)
1???fHm(O2,g)??fHm(CH3OH,l) 2??74.6kJ?mol?1)?0?(?239.2kJ?mol?1)?164.6kJ?mol?1?rHm??fHm(CH4,g)????rSm?Sm(CH4,g)??186.3J?K?1?mol?1????1??Sm(O2,g)?Sm(CH3OH,l)21??205.2J?K?1?mol?1?126.8J?K?1?mol?1?162.1J?K?1?mol?12??rGm??rHm?T?rSm?164.6kJ?mol?1?298.15K?162.1J?K?1?mol?1?116.3kJ?mol?1?0
在298.15K的标准状态下此反应不能自发进行。
(2) ?rGm???rHm??T?rSm??164.6kJ?mol?1?T?162.1J?K?1?mol?1?0
T?1015K
在标准状态下此反应的温度应高于1015K才能自发进行。 11、
?rHm??fHm(H2,g)??fHm(CO2,g)??fHm(H2O,g)??fHm(CO,g)?0?393.5kJ?mol?1)?(?241.8)kJ?mol?1?(?110.5kJ?mol?1)??41.2kJ?mol?1?????
?rGm??fGm(H2,g)??fGm(CO2,g)??fGm(H2O,g)??fGm(CO,g)?0?394.4kJ?mol?1)?(?228.6)kJ?mol?1?(?137.2kJ?mol?1)??28.6kJ?mol?1?????
?rSm?Sm(H2,g)?Sm(CO2,g)?Sm(H2O,g)?Sm(CO,g)?130.7J?K?1?mol?1?213.8J?K?1?mol?1?188.8J?K?1?mol?1?197.7J?K?1?mol?1??42J?K?1?mol?1?????12、(1)
?rGm??fGm(H2O,g)??fGm(H2,g)???228.6kJ?mol?1?G??rmRT??1??fGm(O2,g) 2?0?0??228.6kJ?mol?1?0??228.6kJ?mol?1反应正方向自发。
K??e?e?8.314J?K?1?mol?1?298.15K?1.1?1040
(2) ?rGm?175.2kJ?mol?1?0, 反应逆方向自发。K??2.1?10?31 (3) ?rGm??505.2kJ?mol?1?0, 反应正方向自发。K??3.2?1088 (4) ?rGm??344.8kJ?mol?1?0, 反应正方向自发。K??2.6?1060 (5) ?rGm??227.8kJ?mol?1?0, 反应正方向自发。K??8.2?1039
????6300kJ?250g?3.0kJ?g?1?50g?12kJ?g?113、?6.35L
50.0g?L?1?15.6kJ?g?115、(1) CO2(g)?H2(g)?CO(g)?H2O(g)
(2) CoO(s)?H2(g)?Co(s)?H2O(g)(2) – (1), 得:
(3) CoO(s)?CO(g)?Co(s)?CO2(g)
K3??K1?0.14 K2?67
??K2K1???67?4.8?102 0.14
反应(2)的?rGm?,823??RTlnK2???28.8kJ?mol?1 反应(3)的?rGm?,823??RTlnK3???42.2kJ?mol?1 CO(g)对CoO(s)的还原能力比H2(g)更强。
16、?rGm???RTlnK???RTln
?31.05kJ?mol?1?1[ADP][H3PO4]
[ATP]?13.0?10?3?1.0?10?3 ??8.314J?Kmol?310.15Kln[ATP]解得,[ATP]?1.8?10?11(mol?L?1)
?rGm??rGm?RTlnQ??31.05kJ?mol?1??8.314J?K?13.0?10?3?1.0?10?3 ?mol?310.15K?ln?21.0?10?1??51.97kJ?mol?117、(1) K???[Mn]?2?PCl2100kPa [H?]4[Cl?]2????rGm??fGm(Mn2?,aq)??fGm(Cl2,g)?2?fGm(H2O,l)(2)
??fGm(MnO2,s)?4?fGm(H?,aq)?2?fGm(Cl?,aq)??228.1kJ?mol?1?0?2?237.1kJ?mol?1?465.1?0?2?131.2kJ?mol?1?25.2kJ?mol?1?0???
此反应不能自发进行。
由?rGm???RTlnK?得,K??3.85?10?5
?rGm??rGm?RTlnQ?(3) ?25.2kJ?mol?1?8.314J?K?1?mol?1?298K?ln??11.8kJ?mol?1?01?1 4212.0?12.0反应能自发进行。
?rHm?2??fHm(SO3,g)?2??fHm(SO2,g)??fHm(O2,g)????18、?2?(?395.7kJ?mol?1)?2?(?296.81kJ?mol?1)?0??197.8kJ?mol?1
由lnK2K1???HT?T1?rm(2)得:
RT1T2?K?900K?197.8kJ?mol?1900K?800Kln?()
9108.314J?K?1?mol?1900K?800KK?900K?33.4
19、
?rGm??fGm(Ag?,aq)??fGm(Cl?,aq)??fGm(AgCl,s)?77.1kJ?mol?131.2kJ?mol?109.8kJ?mol?1?1?1?????55.7kJ?mol?1
55.7kJ?mol?1??8.341J?K?1?mol?1?298.15K?lnK?
Ksp(AgCl)?K??1.75?10?10
Exercises
3.
???COCl2(g)?H2O(l)?2HCl(g)?CO2(g)???rGm??fGm(CO2,g)?2??fGm(HCl,g)??fGm(COCl2,g)??fGm(H2O,l)??394.4kJ?mol?1?2?(?95.3kJ?mol?1)?(?210kJ?mol?1)?(?237.1)kJ?mol?1 4. ??137.9kJ?mol?14. 4NO(g)?2N2O(g)?O2(g)
2NO(g)?O2(g)?2NO2(g)(1) ?rGm(1)??139.56kJ?mol?1 (2) ?rGm(2)??69.70kJ?mol?1
??Do the following calculation (2)?2?(1), you get,
2O2(g)?4NO2(g)?2N2O(g)?O2(g), or 2N2O(g)?3O2(g)?4NO2(g)
hence,
?rGm?2??rGm(2)??rGm(1)?2?(?69.70kJ?mol)?(?139.56kJ?mol)?0.16kJ?mol?1?1?1???
5. Qr??rHm??31.4kJ?mol?1
Tb?Qr?rSm?31.4kJ?mol?1??333K ?1?194.2J?K?mol6. According to the isothermal equation of chemical reactions,
?rGm??RTlnK?, substitute the values into the equation,
?50.79kJ?mol?1??8.341J?K?1?mol?1?298K?lnK?
?solve the equation, you get K??7.92?108
The K? value is large, which means that the forward reaction for the
production of methane is favorable, and studying this reaction as a means of methane production is worth pursuing. 7. C57H104O6(s)?80O2(g)?57CO2(g)?52H2O(l)
?rHm?57??fHm(CO2,g)?52??fHm(H2O,l)??fHm(C57H104O6,s)?80??fHm(O2,g)?3.35?104kJ?mol?1?57?(?393.5kJ?mol?1)?52?(?285.8kJ?mol?1)??fHm(C57H104O6,s)?0?fHm(C57H104O6,s)??3.79?103kJ?mol?1
???????8. (1) ?S>0 because of the decreased pressure. (2) ?S>0 because of the change from solid to gas.
(3) cannot be predicted since there is no change in the number of gas molecules.
Chapter 7 Rate of reaction
1?4、略。
5、?(O2)??(SO2)?6.80mol?L?1?h?1
?(SO3)??(SO2)?13.60mol?L?1?h?1
0.6930.693??3.0?10?2d?1 t123d2126、k?7、设反应物消耗99.9%所需时间为t1, 消耗50%所需时间为t2,则:
ln100%0.693?kt2,t2?
(100%?50%)k100%6.90?kt1,t1??10t2
(100%?99.9%)kln8、反应速率常数与反应物浓度无关,则有:
(1)零级反应,k???0.014mol?L?1?s?1
0.014mol?L?1?s?1?1?0.028s(2)一级反应,k?? ?1c0.50mol?L?0.014mol?L?1?s?1?1?1(3)二级反应,k?2? ?0.056mol?L?s?12c(0.50mol?L)?9、由题意知,该反应为一级反应,所求温度下的反应速率常数为
ln1?k2?720s,k2?3.2?10?3s?1 0.1由ln
k2EaT2?T1?()得, k1RT1T2T2?553K3.2?10?314.40kJ?mol?1ln?(), 解得,T2?314K ?2?1?13.5?108.314J?K?molT2?553K1c1?kt求得773K(500℃)和c010、由二级反应的浓度-时间关系式?783K(510℃)下的速率常数分别为:
k773?0.257mol?1?L?s?1,k783?0.378mol?1?L?s?1
由ln ln
k2EaT2?T1?()得, k1RT1T2Ea0.378783K?773K?(),解得Ea?194kJ?mol?1 ?1?10.2578.314J?K?mol783K?773K400℃反应的速率常数求解略。
11、由题意知,该药物的分解反应为零级反应,由零级反应的浓度-时
间关系式c0?c?kt求得276K(3℃)下的速率常数为: k276?9.6?10?4cod?1(设初始浓度为c0, d=day,一年按365天计算)由ln
k2EaT2?T1?()得, k1RT1T2k298135.0kJ?mol?1298K?276Kln?(), ?4?1?1298K?276K9.6?108.314J?K?mol解得298K(25℃)下的速率常数为,k298?7.36?10?2c0d?1
室温下两周后药物的分解率为:
kt7.36?10?2c0d?1?14d??103%,药物已失效。 c0c0(此题答案与教材相差甚远,可能教材按一级反应处理)
12、(1) O2的消耗速率和HbO2生成速率相等,为:
??kc(O2)c(Hb)?1.98?106mol?1?L?s?1?8.0?10?6mol?L?1?1.6?10?6mol?L?1?2.53?10?5mol?L?1?s?1(2)
??kc(O2)c(Hb)1.3?10?4mol?L?1?s?1?1.98?106mol?1?L?s?1?8.0?10?6mol?L?1?c(O2)
解得,c(O2)?8.2?10?6mol?L?1 14、由题意并由ln
lnk2EaT2?T1?()得, k1RT1T2Ea48301K?278K?(), 解得,Ea?75.2kJ?mol?1 ?1?148.314J?K?mol301K?278K15、由Arrhenius方程式得, 无催化剂时,k1?Ae金催化时,k2?Ae铂催化时,k3?Aek2/k1?ek3/k1?e????EaRT?Ae??184kJ?mol?1RT
EaRT?Ae?Ae105kJ?mol?1RT42kJ?mol?1RT
?EaRT?
105kJ?mol?1184kJ?mol?1?RTRT(184?105)kJ?mol?113?exp()?7.0?10 ?1?18.314J?K?mol?298K42kJ?mol?1184kJ?mol?1?RTRT(184?42)kJ?mol?124?exp()?7.8?10
8.314J?K?1?mol?1?298K16、由题意并由lnk2EaT2?T1?()得, k1RT1T2k2k250.0kJ?mol?1313.15K?310.15K,ln?()?0.186?1.20。 ?1?1k18.314J?K?mol313.15K?310.15Kk1 Exercises
2. (1) lnThus, lnc0?kt c2.00?87s?1?0.0010s?0.087 cc?1.83(mol?L?1)
(2) fraction of C4H8 decomposed is:
x?2.00?1.83?0.085 2.003. see the answer in the textbook.
t1(75?C)?20.693?43.0s ?2?11.61?10s4. k?ln0.693?0.116h?1 6hc0?kt?0.116h?1?1h?0.116, cc?89% c0Solve the equation, you get
5、see the answer in the textbook.
Chapter 8 Reodx reactions and electrode potentials
习题
1、K2CrO4: +6;
Na2S2O3: +2 Na2SO3: +4 ClO2: N2O5:
+4 +5
NaH: K2O2:
-1 -1
K2MnO4: +6
2、(1)2MnO4- + 5H2O2 + 6H+ ? 2Mn2+ + 5O2 + 8H2O
(2)Cr2O72- + 3SO32- + 8H+ ? 2Cr3+ + 3SO42- + 4H2O
(3)3As2S3 + 14ClO3- + 8H2O ? 14Cl- + 6H2AsO4 + 9SO42- + 18H+
4、(1)Zn2+ (2)Cl- 5、(-) Zn(s) ? Zn2+ (aq) ?? Ag+ (aq) ? Ag(s) (+) (-) Pt(s) ? Cr2O72-(aq), Cr3+(aq), H+(aq) ?? Cl-(aq) ? Cl2(g)? Pt (+) (-) Pt(s) ? I2(s)? IO3-(aq), H+(aq) ?? Fe3+(aq), Fe2+(aq) ? Pt(s) (+) (1)、(2)反应正向自发;(3)反应逆向自发。 7、两个半反应相减得: 2H2O2(aq) ? 2H2O(aq) + O2(g) E??1.776V?0.695V?1.081V?0 在标准状态下,H2O2能自发分解成H2O和O2。 ?P/P0.05916VH2?(H2/H?)???(H2/H?)?lg2(cH?/c?)28、(1) ?0?0.05916V200kPa/100kPalg??0.068V20.102 ??14(c2?/c)(c?/c)0.05916VHCr2O7?(Cr2O72?/Cr3?)???(Cr2O72?/Cr3?)?lg?26(c3?/c)Cr(2) 0.05916?1.232V?lg(0.0010)14?0.818V6?(Br2/Br?)???(Br2/Br?)?(3) ?1.066V?0.05916V1lg2(cBr?/c?)20.05916V1lg?1.107V220.20 9、 ?(MnO4?/Mn2?)???(MnO4?/Mn2?)??1.507V?0.09466pH0.05916Vlg5(cMnO?/c?)(cH?/c?)84(cMn2?/c?) (1)pH=0.0,?(MnO4?/Mn2?)?1.507V?0.09466pH?1.0507 ?(MnO4?/Mn2?)???(Br2/Br?)???(I2/I?) MnO4-离子能氧化Br-离子和I-离子。 (2)pH=5.5,?(MnO4?/Mn2?)?1.507V?0.09466pH?0.986 ??(Br2/Br?)??(MnO4?/Mn2?)???(I2/I?) MnO4-离子只能氧化I-离子,不能氧化Br-离子。 10、(1)E????(Cl2/Cl?)???(ClO2/ClO2?)?1.358V?0.954V?0.404V ?rGm??nFE???2?96485C?mol?1?0.404V??78.0kJ?mol?1 nE?2?0.404VlgK???13.660.05916V0.05916V??K??4.55?1013 (2)6ClO2(g) + 3H2O ? 5ClO3-(aq) + Cl-(aq) + 6H+ 12、氢电极的电极反应为:2H+(aq) + 2e- ? H2 (g) (c?/c)0.05916V?(H/H2)??(H/H2)??lgH??0.05916V?pH ?2pH2/p??2??由?(H?/H2)??SCE-E?0.2412V?0.420V??0.1788V,得pH?3.02 13、MnO4-、Cr2O72-、H2O2氧化能力减弱,其余不变。 14、 0.05916V0.05916Vlg(cCu2?(右)/c?)???(Cu2?/Cu)?lg(cCu2?(左)/c?)220.05916V0.05916V?lg(1.0?10?1)?lg(1.0?10?4)?0.0887V22E??右??左???(Cu2?/Cu)?右边电极为正极。 0.05916V0.05916Vlg(cCd2?/c?)?(??(Zn2?/Zn)?lg(cZn2?/c?))2215、??0.4030V?0.05916Vlg(0.20)?(?0.7618V?0.05916Vlg(x)) 220.05916V?0.3381V?lg(x)?0.3884V2E???(Cd2?/Cd)? 解得,x=0.020 mol?L-1 16、组成原电池, Hg22+/Hg为正极,Hg2SO4/Hg为负极,组成电池的反应式为: Hg22+ + SO42- ? Hg2SO4 ?n=2 nE?2?(0.797V?0.612V)lgK???6.254 0.05916V0.05916VK?=1.79?106 Ksp(Hg2SO4)=1/ K?=5.59?10-7 ?(Hg2Cl2/Hg)???(Hg2Cl2/Hg)?0.05916V1lg2(cCl?/c?)217、 ?0.0268V?0.05916V1lg2?0.327V2x 解得,x=0.10 mol?L-1 Exercises 1. E????(I2/I?)???(Br2/Br?)?0.5355V?1.066V??0.531V nE?2?(?0.531V)lgK????18.00.05916V0.05916V?K??1.00?10?18 2. K?5?103, therefore, 1?E?lg(5?10)?, E??0.2V 0.05916V3?G???1?96500C?mol?1?0.218V??2?104J?mol?1 3. (1) MnO4- + 3Fe(OH)2 + 2H2O ? MnO2 + 3Fe(OH)3 + OH- MnO4- is the oxidizing agent, Fe(OH)2 is the reducing agent. (2) 2NO3- + 5Zn + 12H+ ? N2 + 5Zn2+ + 6H2O NO3- is the oxidizing agent, Zn is the reducing agent. 4. (1) (-) Al(s) ? Al3+(aq) ?? Cr3+(aq) ? Cr(s) (+) (2) (-) Pt(s) ? SO2(g) ? SO42-(aq), H+(aq) ?? Cu2+(aq) ? Cu(s) (+) 5. E??(Cu2?/Cu)??(SHE) 0.05916Vlg(cCu2?(右)/c?)?0.0000V2 0.05916V?0.342V?lg(cCu2?(右)/c?)?0.25V2???(Cu2?/Cu)?c(Cu2?)?7.8?10?4mol?L?1 6. The overall cell reaction is: Ni2?(aq)?Co(s)?Ni(s)?Co2?(aq) (1) RT8.314J?K?1?mol?1?298K[Co2?]E?E?lnQ?(?0.257V?0.280V)?ln?1nF2?96500C?mol[Ni2?]?8.314J?K?1?mol?1?298K0.2?0.023V?ln0.82?96500C?mol?1?0.041V (2) When [Co2+] reaches 0.4 mol?L-1, 0.4-0.2=0.2 mol?L-1 Co2+ was produced from the reaction in the initial state, thus the concentration of Ni2+ is 0.8-0.2=0.6 mol?L-1. Therefore, RT8.314J?K?1?mol?1?298K0.4E?E?lnQ?0.023V?ln?1nF0.6 2?96500C?mol?0.028V?nE?2?0.023V??0.78, K?6.0 (3) lgK?0.05916V0.05916V(4) RT8.314J?K?1?mol?1?298K[Co2?]E?E?lnQ?0.023V?ln?0.025V ?12?nF2?96500C?mol[Ni]?[Ni2?]?1.17. solve this equation, you get 2?[Co]7. The half-reaction is 2H?(aq)?2e??H2(g) , 0.05916V[H?]20.05916V[H?]2?(H/H2)??(H/H2)?lg?lg?n2p(H2)/100kPap(H2)/p???0.05916V(0.10)2?A(H/H2)?lg??0.058V20.9?101.3kPa/100kPa?0.05916V(2.0)2?B(H/H2)?lg?0.027V 20.5?101.3kPa/100kPa?since ?A(H?/H2)??B(H?/H2), electrode A is the anode. E??B(H?/H2)??A(H?/H2)?0.027V?(?0.058V)?0.085V since E??0V, K?1. 8. The overall cell reaction is: Zn(s)?2H?(aq)?Zn2?(aq)?H2(g) RT8.314J?K?1?mol?1?298K[Zn2?]?p(H2)/p?E?E?lnQ?((0.000V?(?0.762VV))?lnnF2?96500C?mol?1[H?]20.3?101.3kPa0.01?8.314J?K?1?mol?1?298K100kPa?0.762V?ln ?122?96500C?mol2.5?0.860V? Chapter 9 Structures of Atoms and Periodic Table 习题 1、电子波是概率波,反映电子在空间区域出现的概率;而电磁波在 运动过程中是以一种振动的方式行进。 2、1s电子高概率出现的区域是在一球形空间界面内。 h6.626?10?34kg?m2?s?1?93、????1.0?10m?1.0nm ?315?1m?9.1?10kg?7?10m?sh6.626?10?34kg?m2?s?14、????6.6?10?35m,此子弹的波长很小,仅?3?1m?10?10kg?1000m?s表现为粒子性。 h6.626?10?34kg?m2?s?1?30?x???5.3?10m,子弹的位置不 4?m??x4??10?10?3kg?10?3m?s?1确定性和动量不确定性都很小,其运动服从经典力学规律。 5、n、l、m三个量子数决定一个原子轨道,根据Pauli不相容原理, 在一个原子轨道内电子的第四个量子数即自旋量子数必然不同,而自旋量子数只有两个可能取值,因此一个原子轨道最多只能容纳两个2个电子。 6、(1)2p轨道;(2)3d轨道;(3)5f轨道;(4)沿某一空间方向伸 展的2p轨道;(5)4s轨道。 7、2,0,0,?;2,0,0,?;2,1,-1,?;2,1,0,?;2,1,1,?。 8、(1)2s亚层有1个轨道;(2)3f亚层不存在;(3)4p亚层有3个 轨道;(4)5d亚层有5个轨道。 9、 原子序数 49 10 24 电子排布式 [Kr] 4d105s25p1 1s22s22p6 [Ar]3d54s1 价层电子排布 5s25p1 2s22p6 3d54s1 周期 5 2 4 族 IIIA 0 VIB 121212121280 [Xe]4f145d106s2 5d106s2 6 IIB 10、(1)[Ar]3d54s2,5个未成对电子; (2)[Ar]3d104s24p6,没有未成对电子; (3)原子的电子排布式为[Kr]5s2,+2离子的电子排布式为[Kr], 离子没有未成对电子; (4)[Ar]3d104s24p3,3个未成对电子; 11、Ag+:[Kr]4d10;Zn2+:[Ar]3d10;Fe3+:[Ar]3d5;Cu+:[Ar]3d10。 12、该元素原子的电子排布式为[Ar]3d54s1,它在周期表中属于第4周 期、VI B族、d区。由于是d区过渡元素,其前后相邻原子的原子半径约以5pm的幅度递减。 14、各原子按电负性降低次序的排列是:F、S、As、Zn、Ca。理由: 周期表中从左到右电负性递增,从上到下电负性递减。 15、(1)原子价层电子排布是ns2np2,IV A族元素; (2)原子价层电子排布是3d64s2,Fe元素; (3)原子价层电子排布是3d104s1,Cu元素。 16、Fe3+的价层电子排布为3d5, Fe2+的价层电子排布为3d6。根据洪 特规则的特例,d轨道半满时能量较低,较稳定。 Exercises RH12.18?10?18J11114?1(?)?2.34?10s (2?2),得:??1. 由???3422hn16.626?10J?s35n2h6.626?10?34kg?m2?s?1?102. ????1.02?10m?102pm m?1.67?10?27kg?3.90?103m?s?13. For M shell, n=3, so there are 3 subshells; for f subshell, l=3, so there are 2l+1=7 orbitals. 4. (1), (2), and (4) are possible, but they are not the electron configurations of the ground state. (3) is impossible, because 2p subshell can hold on more than 6 electrons. 5. According to the ground-state electron configuration of Thallium, it is a main group element at Period 6, Group III A in the periodic table. 6. (1) Cs, Ba, Sr; (2) Ca, Ga, Ge; (3) As, P, S. Chapter 10 Chemical Bonding and Intermolecular Forces 习题 1、略。 2、略。 3、(1)sp3不等性杂化,三角锥形;(2)sp杂化,直线形;(3)sp3等 性杂化,正四面体;(4)sp3不等性杂化,V形;(5)sp3不等性杂化,三角锥形。 4、见课件。 5、BF3的中心B原子采取sp2杂化,BF3分子的空间构型为平面三角形;而NF3的中心N原子采取sp3不等性杂化,NF3分子的空间构型为三角锥形。 6、(1)中心原子由sp2等性杂化转变为sp3等性杂化,空间构型由平面三角形转变为正四面体;(2)中心原子杂化类型不变,空间构型由V形转变为三角锥形;(3)中心原子由sp3不等性杂化转变为 sp3等性杂化,空间构型由三角锥形转变为正四面体。 7、中心原子的价层电子对构型要同时考虑成键电子对和孤电子对;而分子的几何构型仅考虑成键电子对,即分子中各原子的相对位置。例如,NH3分子的几何构型为三角锥形,而中心N原子的价层电子对构型为四面体构型。 8、(1)CO32-; 离子构型为平面正三角形;中心C原子价层电子对构 型为平面三角形。 (2)SO2; 分子构型为V形;中心S原子价层电子对构型为平面三角 形。 (3)NH4+; 离子构型为正四面体;中心N原子价层电子对构型为正 四面体。 (4)H2S; 分子构型为V形;中心S原子价层电子对构型为四面体。 (5)PCl5; 分子构型为三角双锥;中心P原子价层电子对构型为三角 双锥。 (6)SF4; 分子构型为锯齿形;中心S原子价层电子对构型为三角双 锥。 (7)SF6; 分子构型为正八面体;中心S原子价层电子对构型为正八 面体。 (8)BrF5; 分子构型为四角锥形;中心Br原子价层电子对构型为八 面体。 15、SiF4为正四面体,电偶极矩为零,非极性分子;NF3为三角锥形,电偶极矩不为零,极性分子;BCl3平面三角形,电偶极矩为零,非极 性分子;H2S为V形,电偶极矩不为零,极性分子;CHCl3为四面体,电偶极矩不为零,极性分子。 16、(1)HCl极性强,因为Cl的电负性大; (2)H2O极性强,因为O的电负性大; (3)NH3极性强,因为N的电负性大; (4)非极性分子; (5)CHCl3极性强,因为CH4为非极性分子; (6)NF3极性强,因为BF3为非极性分子。 17、稀有气体的沸点随着分子量的增大而增大。原因:稀有气体为非 极性分子,其可极化性即其分子间作用力(色散力)随着分子量的增大而增大,导致沸点随分子量的增大而增大。 18、(1)H2、Ne、CO、HF;(2)CF4、CCl4、CBr4、CI4。 19、非极性分子的可极化性即分子间作用力(色散力)随分子量增大 而增大。 20、二甲醚为非极性分子,而乙醇为极性分子,乙醇分子间作用力(存 在氢键)比二甲醚大。 21、(1)苯和四氯化碳:色散力; (2)乙醇和水:取向力、诱导力和色散力、分子间氢键; (3)苯和乙醇:诱导力和色散力; (4)液氨:取向力、诱导力和色散力、分子间氢键。 22、HF与HF > H2O与H2O > NH3与NH3 23、(1)A原子采取sp3等性杂化; (2)A-B为极性键,AB4为非极性分子; (3)AB4非极性分子间仅存在色散力; (4)经推测AB4为CCl4,因此其熔点和沸点都比SiCl4低。 Exercises 1. (1) HgCl2: sp hybridization. The molecule has a linear geometry. 6p6s6p6ssp(2) AlI3: sp2 hybridization. The molecule has a trigonal planar geometry. 3p3s3p3ssp2(3) PF3: sp3 hybridization. The molecule has a trigonal pyramidal geometry. 3p3ssp32. (a) AsH3: four valence-shell electron pairs, three H atoms are bonded, the molecule has a trigonal pyramidal geometry. (b) OF2: four valence-shell electron pairs, two F atoms are bonded, the molecule has a bent geometry. (c) AlCl4-: four valence-shell electron pairs, four Cl atoms are bonded, the molecule has a tetrahedral geometry. (d) I3-: five valence-shell electron pairs, two I atoms are bonded, the molecule has a linear geometry. 5. F- and HCOOH. Chapter 11 Coordination Compounds 习题 1、略。 2、 名称 中心原子 (1)二(硫代硫酸根)合银(I)酸钠 Ag+ (2)硫酸三(乙二胺)合钴(III) Co3+ (3)四羟基合铝(III)酸 Al3+ (4)六氟合硅(IV)酸钠 Si(IV) (5)五氯?氨合铂(IV)离子 Pt4+ (6)氯?硝基?四氨合铂(II) Pt2+ (7)氯化二氯?三氨?水合钴(III) Co3+ (8)四(异硫氰酸根) ?二氨合铬(III)酸铵 Cr3+ 3?配体 S2O32- en OH- F- Cl-, NH3 Cl-, NO2-, NH3 Cl-, NH3, H2O NCS-, NH3 3?配位原子 S N O F Cl, N Cl, N, N Cl, N, O N, N ?配位数 2 6 4 6 6 6 6 6 [Ag(S2O3)2][Co(en)3][Al(OH)4]K?K?K?(1) s (2) s (3) s 2?[Co3?][en]3[Al3?][OH?]4[Ag?][S2O3]2[PtCl5(NH3)?][SiF6](4) Ks?4??6 (5) Ks?4? ?5[Pt][Cl][NH3][Si][F]2?[Pt(NH3)4(NO2)Cl][CoCl2(NH3)3H2O?](6) Ks?2? (7) Ks? ?3??232?4[Co][Cl][NH3][HO][Pt][Cl][NO2][NH3][Cr(NCS)4(NH3)2](8) Ks?3??42 [Cr][NCS][NH3]?3、略 4、(1)错。配位分子没有外层离子。 (2)错。中心原子也可以是非金属元素,如第2题中的第(4)小题。 (3)错。如配体均为单齿配体时,该说法成立。 (4)错。配体的带电性质也会影响配离子的电荷数。 5、(1)[PdCl4]2-为平面四方形结构,中心Pd原子采取dsp2杂化,其 电子排布为: [Kr]4ddsp25p配离子中无单电子,? = 0, 配离子为抗磁性。 (2)[Cd(CN)4]2-为四面体结构,中心Cd原子采取sp3杂化,其电子排布为: [Kr]4dsp3配离子中无单电子,? = 0, 配离子为抗磁性。 [HgY2?][NH3]4[HgY2?][Hg2?][NH3]4K??2?2?2?4?4?[Hg(NH3)4][Y][Hg][Y][Hg(NH3)4]?Ks([HgY])10??102.4??12?19.3Ks([Hg(NH3)4])102?21.712、(1) Ks([Zn(NH3)4]2?)109.46(2) K??13.32?10?3.86??1 2?Ks([Cu(NH3)4])10Ks([Fe(CN)6]3?)1035(3) K??20.2?1014.8??1 3?Ks([Fe(C2O4)3])10 由此可知,反应(1)和(3)正向进行,反应(2)逆向进行,反应(3)正向 进行得最完全。 13、(1) c(Cu2?)?0.050mol?L?1, c(OH?)?0.050mol?L?1 Ip[Cu(OH)2]?c(Cu2?)?c2(OH?)?0.0503?1.3?10?4?Ksp[(Cu(OH)2]?2.2?10?20 应该会出现Cu(OH)2沉淀。 (2) [Cu(NH3)4]2+的初始浓度为0.050 mol?L-1,假设[Cu(NH3)4]+分解生成x mol?L-1Ag+。则有: 浓度 (mol·L-1) [Cu(NH3)4]2+ ? Cu2+ + 4NH3 初始浓度 浓度变化 平衡浓度 0.050 -x 0.050-x 0 +x x 0 +4x 4x 假定x远小于0.050,则有: 0.050?1013.32解得,x?3.9?10?4 4x?(4x)Ip[Cu(OH)2]?c(Cu2?)?c2(OH?)?3.9?10?4?0.0502?9.8?10?7?Ksp[(Cu(OH)2]?2.2?10?20应该会出现Cu(OH)2沉淀。 (3) c(Cu2?)?0.100.1??0.044(mol?L?1), c(OH?)?0.025mol?L?1 24?4Ip[Cu(OH)2]?c(Cu2?)?c2(OH?)?0.044?0.025?0.025?2.8?10?5?Ksp[(Cu(OH)2]?2.2?10?20 应该会出现Cu(OH)2沉淀。 14、 [Ni(NH3)6]2+ + 3 en ? [Ni(en)3]2+ + 6 NH3 [Ni(en)3][NH3]611018.332?K??Ks[Ni(en)3]??8.74?3.89?109 2?62?3[Ni(NH3)6][en]Ks[Ni(NH3)6]102?由于K值远远大于1,计算过程中先假定Ni(NH3)62+完全转化为Ni(en)32+,即Ni(NH3)62+的浓度为0 mol?L-1,NH3的浓度为(1.00+0.10?6) = 1.60 mol?L-1,Ni(en)32+的浓度为0.10 mol?L-1,en的浓度为(2.30-0.10?3) = 2.00 mol?L-1。然后Ni(en)32+极少量(设为x)转化为Ni(NH3)62+,则有: 浓度 (mol·L-1) 初始浓度 浓度变化 平衡浓度 2?[Ni(NH3)6]2+ + 3 en ? [Ni(en)3]2+ + 6 NH3 0 2.00 0.10 1.60 x +3x -x -6x x 2.00+3x 0.10-x 1.60-6x [Ni(en)3][NH3]6(0.10?x)(1.60?6x)699?3.89?10由,得 ?3.89?102?633x(2.00?3x)[Ni(NH3)6][en]0.10?(1.60)6因x?0,方程简化为?3.89?109, 3x(2.00)解得x?5.4?10?11(mol?L?1) 即Ni(NH3)62+的浓度为5.4×10-11 mol?L-1,NH3的浓度为1.60 mol?L- 1 ,Ni(en)32+的浓度为0.10 mol?L-1,en的浓度为2.00 mol?L-1。 15、(1)稀释后溶液中Ag+的浓度为0.050 mol?L-1,NH3的浓度为: 30.00mL?0.929kg?L?1?18.3%计算过程中先假定Ag+完?3.00mol?L?1。?117.0g?mol?100mL全与NH3形成Ag(NH3)2+,即Ag(NH3)2+的浓度为0.050 mol?L-1,NH3的浓度为(3.00-0.050?2) = 2.90 mol?L-1,然后Ag(NH3)2+分解生成x mol?L-1Ag+。则有: 浓度 (mol·L-1) 初始浓度 浓度变化 平衡浓度 Ag(NH3)2+ ? 0.050 -x 0.050-x Ag+ + 0 +x x ?2NH3 2.90 +2x 2.90+2x [Ag(NH3)2]0.0507?1.1?10假定x远小于0.050,则由得:?Ksx?(2.90)2[Ag?][NH3]2解得,x?5.4?10?10 则溶液中Ag+、Ag(NH3)2+、NH3的浓度分别为5.4?10-10 mol?L-1、0.050 mol?L-1、2.90 mol?L-1。 (2)加0.100 mol?L-1 KCl溶液10.0 mL时,Cl-的最终浓度为0.0100 mol?L-1,则: Ip(AgCl)?c(Ag?)?c(Cl?)?5.4?10?10?0.0100?5.4?10?12?Ksp(AgCl) 所以无AgCl沉淀生成。 若溶液中无AgCl沉淀生成时, c(Ag)??Ksp(AgCl)c(Cl?)?1.77?10?10??1.77?10?8(mol?L?1) 0.0100[Ag(NH3)2]0.050?1.1?107 ?K据得,s?82?21.77?10?[NH3][Ag][NH3]解得,[NH3] = 0.51 (mol?L-1) 16、计算步骤同15题(1)小题。简单求解如下: 混合后溶液中CN-、Ag+初始浓度分别为0.135 mol?L-1、0.0461 mol?L-1。先假定Ag+完全与CN-形成[Ag(CN)2]-,然后[Ag(CN)2]-分解生成x mol?L-1Ag+。则有: 浓度 (mol·L-1) 初始浓度 浓度变化 平衡浓度 [Ag(CN)2]- ? 0.0461 -x 0.0461-x Ag+ + 0 +x x 2CN- 0.135-2?0.0461=0.043 +2x 0.043+2x ? [Ag(CN)2]0.0461?1.3?1021 假定x远小于0.0461,则由得:?Ks2??2x?(0.043)[Ag][CN]解得,x?1.9?10?20 因此,溶液中Ag+、[Ag(CN)2]-、CN-的浓度分别为1.9?10-20 mol?L-1 、0.0461 mol?L-1、0.043 mol?L-1。 23、[Ag(NH3)2]+ + 2 S2O32- ? [Ag(S2O3)2]3- + 2 NH3 K?Ks[Ag(S2O3)23?12.9?1013]???2.64?106 ?7Ks[Ag(NH3)2]1.1?10由题意知,[Ag(NH3)2]+完全转化为Ag(S2O3)2]3-时,[Ag(NH3)2]+的浓度为10-5 mol?L-1,[Ag(S2O3)2]3-的浓度约为0.1 mol?L-1,NH3的浓度约为0.2 mol?L-1。设加入的S2O32-浓度为 x mol?L-1,则有: 浓度 (mol·L-1) 初始浓度 浓度变化 平衡浓度 [Ag(NH3)2]+ + 2S2O32- ? [Ag(S2O3)2]3- + 2 NH3 0.10 x 0 0 -0.10 -0.20 +0.10 +0.20 10-5 x-0.20 0.10 0.20 0.10?(0.20)2?16x?0.212(mol?L) 由?5,解得?2.64?10210?(x?0.20)S2O32-的平衡浓度约为(0.212-0.20)=0.012 (mol?L-1)。 Exercises 1. c = 0.10 mol?L-1, b ? 0.10 mol?kg-1 Assume the van’t Hoff factor is i, thus, ?Tf?Kf?i?b, 0.56K?1.86K?kg?mol?1?i?0.10mol?kg?1 i?3 The correct formula of the compound is [Co(NH3)4(H2O)Cl]Cl2. 3. c(Ag+) = 0.05000mol?L-1, c(Cl-) = 0.05000mol?L-1 To be sure no precipitate of AgCl is formed, [Ag]??Ksp(AgCl)[Cl?]1.77?10?10??3.54?10?9 , which indicates that almost all 0.05000Ag+ exists in the forms of [Ag(NH3)2]+, or [Ag(NH3)2+]=0.05000 mol?L-1, Assume [NH3] = x mol?L-1, thus, [Ag(NH3)2]?Ks ?2[Ag][NH3]?0.05000?1.1?107 ?923.54?10?xx?1.13(mol?L?1) The concentration of NH3 should be higher than 1.13 mol?L-1 in the solution. 4. Ag+ + 2CN- ? [Ag(CN)2]- 0.1[Ag(CN)2]21.110?, , [Ag?]?10?20.1 Ks[Ag(CN)2]??2??2[Ag][0.1][Ag][CN]??Ip(AgI)?c(Ag?)?c(I?)?10?20.1?0.1?10?21.1?Ksp(AgI)?8.52?10?17 Therefore, AgI will not precipitate out. 5. [Ag(CN)2]- + 2NH3 ? [Ag(NH3)2]+ + 2CN- K?[Ag(NH3)2][CN?]2[Ag(CN)2][NH3]2???[Ag(NH3)2][Ag?][CN?]2?? ?2?[Ag][NH3][Ag(CN)2]?1.1?107??8.5?10?15??1 ?Ks[Ag(NH3)2]?21?Ks[Ag(CN)2]1.3?101The reverse reaction is spontaneous. Chapter 12 Volumetric Analysis 习题 1、(1)5;(2)3;(3)2;(4)1;(5)2。 2、 0.0002g?0.2g 0.1%3、甲 0.3610, 0.3612, 0.3603 Er甲?x?0.3608 ?100%?0.12% 0.3610?0.3606?0.3612?0.3606?0.3603?0.36063?0.36060.3610?0.3608?0.3612?0.3608?0.3603?0.36083?0.3608dr甲??100%?0.10% 乙 0.3641, 0.3642, 0.3643 Er乙?x?0.3642 ?100%?1.0% 0.3641?0.3606?0.3642?0.3606?0.3643?0.36063?0.36060.3641?0.3642?0.3642?0.3642?0.3643?0.36423?0.3642dr乙??100%?0.02% Er甲 5、pKIn??log(1.3?10?5)?4.89;pKHIn?14.00?pKIn?14.00?4.89?9.11 ?? 6 此指示剂的变色范围为8.11 ? 10.11。 、 n(HCl)2n(Na2CO3)??V(HCl)V(HCl)2?1.3350g25.00mL?106.0g?mol?1250.0mL?0.1028mol?L?1 24.50mLc(HCl)?1m(H2C2O4?2H2O)?c(NaOH)?V(NaOH)?M(H2C2O4?2H2O)27、(1) 1?0.1mol?L?1?25mL??136g?mol?1?0.17g2 相对误差为: ?0.0001g?100%??0.06%??0.05% 0.17g(2)若改用邻苯二甲酸氢钾,则有: m(KHC8H4O4)?c(NaOH)?V(NaOH)?M(KHC8H4O4)?0.1mol?L?25mL?204g?mol?1?1?0.51g 相对误差为: ?0.0001g?100%??0.02%??0.05% 0.51g8、略 9、加入40.00mL NaOH溶液时达到化学计量点,此时弱酸与恰好完 全与NaOH反应。当加入16.00mL NaOH时,溶液中弱酸与其共轭碱的浓度比应为: 40.00?16.003? 16.002由缓冲溶液pH计算公式得: pH?pKa?lg[base]2,即6.20?pKa?lg [acid]3解得,Ka?4.2?10?7 10、根据Ka?c是否大于10-8判断是否可直接滴定。一元酸只有一个滴定突跃,二元酸根据相邻Ka比值是否大于104判断是否可进行分步滴定。计算步骤略。 11、略。见教材答案。 12、第一步滴定将溶液中的Na2CO3滴定为NaHCO3,第二步滴定将 第一步生成的NaHCO3和溶液中原来存在的NaHCO3滴定为H2CO3,因此样品中Na2CO3和NaHCO3质量分数分别为: 23.10mL?0.2000mol?L?1?106.0g?mol?1?(Na2CO3)??100%?71.61% 0.6839g(26.81?23.10)mL?0.2000mol?L?1?84.01g?mol?1?(NaHCO3)??100%?9.11%0.6839g13、 (50.00mL?0.2500mol?L?1?2?0.5000mol?L?1?1.56mL)?17.03g?mol?1?(NH3)??100%?41.25%1.000g14、 n(N)?n(HCl)??n总(HCl)?n余(HCl)???n总(HCl)?n余(HCl)???C(NaOH)?V(NaOH)?C(NaOH)?V返(NaOH)?1L1L???0.07893mol?L?1??15.83mL??13.12mL??1000mL1000mL???0.2139?10-3molM(N)?n(N)14.00g?mol?1?0.2139?10-3mol?(N)???6.304?10-3m(N)0.4750g 15、 n(C9H8O4)?n(NaOH)1L1000mL?0.9500?(C9H8O4)?M(C9H8O4)?n(C9H8O4)?m总180.0g?mol?1?0.1032mol?L?1?21.08mL?0.4122g16、2KMnO4?5H2O2?3H2SO4?2MnSO4?K2SO4?5O2?8H2O 试样中过氧化氢的质量分数为: 5250mL0.02732mol?L?1?35.86mL??34.00g?mol?1?225.00mL?100%?3.331% 25.00mL?1.000g?mL?1 17、Ca2??C2O42??CaC2O4 CaC2O4?H2SO4?H2C2O4?CaSO4 2KMnO4?5H2C2O4?3H2SO4?2MnSO4?10CO2?K2SO4?8H2O 550.00mL100mL0.00200mol?L?1?1.15mL??40.0g?mol?1???0.0230g?23.0mg 210.00mL5.00mLExercises 1. 29.837?29.240.60??0.019 32.06532.0652. (a) HX is weaker because its conjugate base is stronger (pH=8.8) than Y-(pH=7.9). (b) Phenolphalein should be used as the indicator. 3. M(HX)?m(HX)m(HX)0.1276g???109.6g?mol?1 ?1n(HX)n(NaOH)18.40mL?0.06330mol?L[X?] [HX]pH?pKa?lg5.87?pKa?lg10.00 Ka?1.6?10?6 18.40?10.004. m(H2C2O4?2H2O)?250.0mL?0.1000mol?L?1?126.0g?mol?1?3.150g 5. 2NaOH?H2SO4?Na2SO4?2H2O The moles of NaOH is equal to twice the moles of H2SO4 used to titrate it, since they react in a 1:2 ratio. 13.40mL?0.05550mol?L?1c(NaOH)??2?0.05950mol?L?1 25.00mL6. (a) same steps as in Exercise 3. 21.28mL?0.1024mol?L?1c(NaOH)??2?0.2240mol?L?1 19.46mL(b) m(NaOH)?0.2240mol?L?1?1L?40.00g?mol?1?8.960g 7. The first end point corresponds to that in the titration of Na2CO3 to NaHCO3. Therefore, the moles Na2CO3 is the same as the moles HCl used in the 15.70 mL titration. The NaHCO3 produced from the first-step titration and NaHCO3 present in the original sample are titrated together. A 15.70 mL portion of HCl was used to titrate the NaHCO3 produced from the first-step titration, leaving (43.80 - 15.70 - 15.70) = 12.40 mL used to titrate the NaHCO3 present in the original sample. Therefore, 15.70mL?0.1090mol?L?1?106.0g?mol?1%Na2CO3??100%?31.71% 0.5720g12.40mL?0.1090mol?L?1?84.01g?mol?1%NaHCO3??100%?19.85% 0.5720gChapter 13 UV-Vis spectrometry 习题 1、略。 2、略。 3、略。 4、略。 5、当浓度为c2 = 0.5c1时,A2 = 0.5A1, 则T2 = T11/2; 当浓度为c3 = 2c1时,A3 = 2A1, 则T3 = T12; T2最大。 0.500?g55.8g?mol?12??8.96?10?6mol?L?1 6、c(Fe)?1mL 由A??bc得:??A0.1984?1?1 ??1.10?10L?mol?cm?6?1bc2.00cm?8.96?10mol?L7、假设服从Beer定律,则有: A2?A1b20.1205????0.100?0.200,所以不服从Beer定律。 2b1238、c?A0.687?4?1 ??9.77?10mol?L?1?1?b703L?mol?cm?1.00cm m(托巴丁胺)?9.77?10?4mol?L?1?2.00L?270g?mol?1?0.528g 9、c? A0.600?6?1 ??2.4?10mol?L5?1?1?b2.5?10L?mol?cm?1.00cmm?2.4?10?6mol?L?1?200?1L?125g?mol?1?0.0600g 10、当溶液液层厚度为1.0cm时,T = 50%, A = -lgT = 0.301 由此可知,当溶液液层厚度为2.0cm时, A = 2 ? 0.301 = 0.602,T?10?0.602?0.250?25% 11、由题意知,1.00 mL伊凡氏蓝稀释至5.00 L后,其吸光度为0.200, 1.00 mL伊凡氏蓝在血浆中稀释后吸光度为0.380,由此求得血浆 0.200?5.00L?2.63L。血浆占全血53%,因此人体中血液0.3802.63L的容量为 = 5.0 L。 53%的体积为 12、假定样品中维生素C的质量为m, m(Vc)2.00mL样品检测时,c(Vc)?Mr? V100.0mL因为: A??bcE1m???10 Mr1mm(Vc)E?Mr2.00mL所以,A??bc? ?b?Mr?10V100.0mL即 m(Vc)560L?g?cm?Mr2.00mL0.551??1.00cm?Mr?100.100L100.0mL m(Vc)?0.0491g m(Vc)0.0491g?(Vc)?==0.982m样0.0500g?1?1Exercises 2. In the case of 1 cm pathlength of the solution, A??lgT??lg0.25?0.60, When the pathlength of the solution is changed to 2 cm, the aborbance doubles, A?2?0.60?1.2 . The correspondent transmittance is T?10?A?10?1.2?0.063?6.3% 3. see class example 13-2.