12. For a spontaneous endothermic process, which conditions must hold?

(1)  = △G (2)  ＞ 0 (3) △S cannot be negative (4) △S is positive.
(A) all
(B) none
(C) 1 and 3 only
(D) 1, 2, and 4 only
(E) 3 and 4 only

8. As water is heated, its pH decreases. This means that (A) the water is no longer neutral (B) (C) two of these are correct (D) none of these is correct

9. The acids HC2H3O2 and HF are both weak, but HF is a stronger acid than HC2H3O2. HCl is a strong acid. Order the following according to base strength. (A) (B) (C) (D) F¯ ＞ (E) none of these

10. For which of the following reaction(s) is the enthalpy change for the reaction not equal to of the product? I: 2H(g) → H2(g), II: H2(g) + O2(g) → H2O2(1), III: H2O(l) + O(g) → H2O2(1) (A) I only (B) II only (C) III only (D) I and III (E) II and III

11. For a particular process q = -10 kJ and w = 25 kJ. Which of the following statements is true? (A) heat flows from the surroundings to the system (B) the system does work on the surroundings (C) ΔΕ = −35 kJ (D) all of these are true (E) none of these is true

13. Choose the correct statement. (A) exothermic reactions are always spontaneous (B) free energy is independent of temperature (C) a reaction that exhibits a negative value of AS cannot be spontaneous (D) at constant pressure and temperature, a decrease in free energy ensures an increase in the entropy of the system (E) none of these

14. When the equation for the following reaction in basic solution is balanced, what is the sum of the coefficients? (A) 11 (B) 31 (C) 14 (D) 9 (E) 18

15. From the following list of observations, choose the one that most clearly supports the conclusion that electrons have wave properties. (A) the emission spectrum of hydrogen (B) the photoelectric effect (C) the scattering of alpha particles by metal foil (D) diffraction (E) cathode "rays"

16. Which of the following statements is true? (A) we can determine the exact location of an electron if we know its energy (B) an electron in a 2s orbital can have the same n, l, and m₁ quantum numbers as an electron in a 3s orbital (C) Ni has 2 unpaired electrons in its 3d orbitals (D) in the building up of atoms, electrons occupy the 4f orbitals before the 6s orbitals (E) only three quantum numbers are needed to uniquely describe an electron

17. Which of the following combinations of quantum numbers do not represent permissible solutions of the Schrodinger equation for the electron in the hydrogen atom? (In other words, which combination of quantum numbers is not allowed?) (Combinations are listed as follows: n, l, m(1), M(s).) (A) 9, 8, 4, 1/2 (B)8, 2, 2, 1/2 (C) 6, -5, -1, 1/2 (D) 6, 5, −5, 1/2 (E) all are allowed

18. For which element are the d orbitals completely filled in the neutral atom? (A) potassium (B) vanadium (C) phosphorus (D) iron (E) bromine