课程名称︰普通化学丙
课程性质︰必修
课程教师︰佘瑞琳
开课学院：理学院
开课系所︰化学系
考试日期（年月日）︰103/10/6
考试时限（分钟）：110分钟
试题 :
General Chemistry Midterm Exam 2014/10/06
Gas constant: R = 8.314 J/mol.K = 0.082 L.atm/mol.K; 1 L.atm = 101.3 J
Ⅰ. Multiple choices questions (30%, 2 points per question, each may have 1-4
correct answers)
1. For the following measurements, which one shows four significant figures?
(a) 8.501 g (b) 0.0851 g (c) 8.500 x 10^-2 g (d) 8.510 g
2. Which of the following calculations show two significant figures in the
answer?
(a) 66 + 55 (b) 257 - 11 (c) 257 x 11
(765-22) x 315.1
(d) －－－－－－－－－－
0.11 x 273
3. Which of the following is the intensive property?
(a) melting point (b) density (c) mass (d) volume
4. Choose the correct conversion in the followings:
(a) 33 nm = 3.3 x 10^-9 m (b) 0.015 g = 15 mg (c) 6 μL = 6 x 10^-6 L
(d) 45 ℃ = 81 ℉
56 3+
5. For the ion Fe , which of the following statement is correct?
26
(a) the proton number is 26 (b) the mass number is 56
(c) the number of electrons is 26 (d) the number of neutrons is 26.
6. Which of the following is noble gas?
(a) N2 (b) O2 (c) Cl2 (d) Xe
7. Solubility rules predict precipitate formation for mixing 0.1 M aqueous
solutions of
(a) H2SO4 and Ba(OH)2 (b) NaCl and Mg(NO3)2 (c) and CuCl2 (d) HCI and AgNO3
8. Which of the following is strong electrolyte?
(a) HF (b) NH3 (c) HCOOH (d) HClO4
9. Which of the following underlined atoms show the highest oxidation number?
(a)H2CO3 (b) KCrO4 (c) HNO2 (d) H2O2
2- - + 2+
10.Consider the reaction: C2O4 + MnO4 + H → CO2 + Mn + H2O (unbalanced)
+ -
(a) H is reduced. (b) MnO4 is oxidized.
2- -
(c) C2O4 is reducing agent. (d) MnO4 is oxidant.
11.For 25.00 mL of HCl(aq) with unknown concentration is titrated to the
equivalence point with 15.24 mL of 0.1210 M Ba(OH)2? What's the
concentration of the unknown acid?
(a) 0.07376M (b) 0.1475M (c) 0.2420M (d) can't be determined
12.Consider 4.0 g of He, H2 and O2 gases are in separated containers with the
same volume and the same temperature. Which of the following quantities will
be equal to each other?
(a) pressure (b) average kinetic energy (c) density
(d) root-mean-square speed.
13.The valve between a 5.0-L tank containing O2 gas at 9.0 atm and a 10.-L tank
containing N2 gas at 6.0 atm is opened. http://ppt.cc/hiUk
(a) The partial pressure of O2 is kept at 9.0 atm
(b) The partial pressure of N2 is kept at 6.0 atm
(c) The mole fraction of N2 is 0.57.
(d) The final pressure in the tanks is 15.0 atm.
14.According to the plots of relative molecular speed distribution of UF6
(Mw: 352 g/mol) and H2 (Mw: 2.01 g/mol) gas at 273 K,
http://ppt.cc/QBHl
(a) The relative molecular speed distribution of UF6 is Plot (I).
(b) The root-mean-square speed of H2 is greater than UF6.
(c) The average kinetic energy of H2 is greater than UF6.
(d) The rate of effusion of UF6 is greater than H2.
15.Which of the following set is structural isomers?
(a) CH3OCH3, CH3CH2OH (b) n-hexane, 2-methylpentane
(c) http://ppt.cc/29QU (d) CH3CH＝CHCH3, http://ppt.cc/4yHF
Ⅱ. Problems (70%)
l. Give the systematic name of the following compounds: (10%)
(a) HBr(aq) (b) CoSO4 (c) KH2PO4 (d) N2O5 (e) HClO2
2. Write the chemical or structural formula of the following compounds: (10%)
(a) 2-propanol (b) trans-2-butene (c) 2,2-dimethylheptane
(d) ferrous chloride (e) sodium bicarbonate
3. Identified and name the functional groups of the compound: (4%)
http://ppt.cc/JNI5
4. Menthol (M = 156.3 g/mol), the strong-smelling substance in many cough
drops, is a compound of carbon, hydrogen, and oxygen. When 0.1595 g of
menthol was burned in a combustion apparatus, 0.449 g of CO2 and 0.184 g of
H2O formed. What is menthol's molecular formula? (10%, 3.34)
5. A sample of concentrated nitric acid has a density of 1.41 g/mL and contains
70.0% HNO3 by mass. (a) What mass (g) of HNO3 is present per liter of
solution? (b) What is the molarity of the solution? (c) Calculate the mole
fraction of HNO3 in this solution. (10%, 3.72)
-
6. The mass percent of Cl in a seawater sample is determined by titrating
25.00 mL of seawater with AgNO3 solution, causing a precipitation reaction.
+
An indicator is used to detect the end point, which occurs when free Ag ion
-
is present in solution after all the Cl has reacted. If 55.75 mL of 0.2850 M
-
AgNO3 is required to reach the end point, what is the mass percent of Cl in
the seawater (d of seawater = 1.024 g/mL) (10%, 4.32)
7. Copper reacts with any oxygen present as an impurity in the ethylene used to
make polyethylene. The copper is regenerated when hot H2 reduces the
copper(II) oxide, forming the pure metal and H2O. (a) Write the balanced
chemical reaction equation. (b) What volume of H2 at 765 torr and 225 ℃ is
needed to reduce 35.5 g of copper(II) oxide? (10%, p. 168)
8. Write the van der Waals equation for a real gas. Explain briefly the meaning
of the corrective terms for pressure and volume. (6%, p. 179)