所屬科目:研究所、轉學考(插大)◆普通化學
1. The empirical formula of styrene is CH; its molar mass is 104.1 g/mol. What is the molecular formula of styrene? (A) C2H4 (B) C8H8 (C) C10H12 (D) C6H6
2. What type of reaction always produce water? (A) Precipitation (B) Acid-Base (C) Decomposition (D) Synthesis
3. Which of the following statements about quantum theory is incorrect? (A) No two electrons can have the same four quantum numbers. (B) The energy and position of an electron cannot be determined simultaneously. (C) Lower energy orbitals are filled with electrons before higher energy orbitals. (D) When filling orbitals of equal energy, two electrons will occupy the same orbital before filling a new orbital. (E) All of these are correct.
4. Sodium losing an electron is an ________ process, and fluorine losing an electron is an _______ process. (A) exothermic, endothermic (B) endothermic, exothermic (C) exothermic, exothermic (D) endothermic, endothermic (E) More information is needed.
5. Which of the following compounds will NOT show the precipitation? (A) AgNO3 + HCl (B) Hg(NO3)2 + HCl (C) Pb(NO3)2 + Na2S (D) Hg(NO3)2 + Na2S
6. Which of the following atoms or ions has three unpaired electrons? (A) N (B) O (C) Al (D) S2 – (E) I3 –
7. If n = 3, how many orbitals are possible? (A) 3 (B) 4 (C) 8 (D) 9 (E) 6
8. Equilibrium is reached in chemical reactions when: (A) All chemical reactions stop. (B) The concentrations of reactants and products become equal. (C) The rates of the forward and reverse reactions become equal. (D) The temperature shows a sharp rise. (E) The forward reaction stops.
9. Which of the following bonds is least polar? (A) C—O (B) H—C (C) Cl—Cl (D) S—Cl (E) They are all nonpolar.
10. Which of the following is the empirical formula of glucose, C6H12O6? (A) C3H6O3 (B) C6H12O6 (C) CH4O (D) CH2O
11. Rank the following compounds according to increasing solubility in water.I. CH3–CH2–CH2–CH3 II. CH3–OH III. CH3–CH2–OH IV. CH3–CH2–O–CH2–CH3 (A) I < IV < III < II (B) I < II < IV < III (C) III < IV < II < I (D) I < II < III < IV (E) None of these (A-D) is correct.
12. What is the oxidation state of chromium in K2CrO4? (A) 4 (B) -2 (C) 3 (D) 6
13. Consider equal mole samples of N2O, Al(NO3)3, and KCN. Which one has the most number of nitrogen atoms in each sample? (A) N2O (B) Al(NO3)3 (C) KCN (D) All are the same
14. In the reaction CH4(g) + 2 O2(g) → CO2(g) + 2 H2O(g), methane is __________. (A) the reducing agent (B) the electron acceptor (C) reduced (D) the oxidizing agent (E) more than one of these
15. Which of these is an isoelectronic series? (A) Na+ , K+ , Rb+ , Cs+ (B) K+ , Ca2+, Ar, S2– (C) Na+ , Mg2+, S2–, Cl– (D) Li, Be, B, C (E) None of these (A-D)
16. How many of the following molecules have dipole moments? BH3, NH3, PCl5, H2O, HF, H2 (A) 1 (B) 2 (C) 3 (D) 4 (E) 5
17. How many of the following molecules (or ions) are linear?NO2 – , C2H2, N3 – , HCN, CO2, H2O2 (A) 2 (B) 3 (C) 4 (D) 5 (E) 6
18. The bond angles about the carbon atom in an ethylene, H2C=CH2, are about: (A) 120° (B) 60° (C) 109° (D) 180° (E) 90°
19. The hybridization of the central atom in N3 - is: (A) sp (B) sp2 (C) sp3 (D) dsp3 (E) d 2 sp3
20. Which of the following substances contains two pi bonds? (A) C2H4 (B) C3H8 (C) C2H2 (D) C2H6 (E) CH4
21. In the molecule C2H4 the valence orbitals of the carbon atoms are assumed to be (A) not hybridized (B) sp hybridized (C) sp2 hybridized (D) sp3 hybridized (E) dsp hybridized
22. Which of the following does not contain at least one pi bond? (A) H2CO (B) CO2 (C) C2H2 (D) C4H10 (E) All of the above (A-D) contain at least one pi bond
23. In a 0.1 molar solution of NaCl in water, which one of the following will be closest to 0.1? (A) The mole fraction of NaCl. (B) The mass fraction of NaCl. (C) The mass percent of NaCl. (D) The molality of NaCl. (E) All of these are about 0.1.
24. Which of the following chemical or physical changes is an endothermic process? (A) the mixing of sulfuric acid and water (B) the evaporation of water (C) the freezing of water (D) the combustion of gasoline (E) none of these
25. What is the probability of finding a particle in a one-dimensional box in energy level n = 4 between x = 0 and x = L/2? (L is the length of the box.) (A) 50% (B) 25% (C) 12.5% (D) 33% (E) 37.5%