Question

6) Which of the following statements is true? A) If Q = K, it means the reaction is not at equilibrium B) If Q< K, it means the forward reaction will proceed (to the right) to form more reactants. C) If Q< K, it means the reverse reaction will proceed (to the left) to form more reactants. D) If Q> K, it means the forward reaction will proceed (to the right) to form more reactants E) If Q> K, it means the reverse reaction will proceed (to the left) to form more reactants 7) The following reaction is exothermic. Which change will shift the equilibrium to the left? 2 NO2(8) N;O4(g) 7) A) decreasing the temperature B) adding NO2(g) C) removing N2O4(g) D) increasing the volume (decreasing the E) adding neon pressure) 8) Determine the pH of a 0.550 M solution of a weak acid whose Ka is 3.8 x 10 D) 5.68 B) 2.09 x 10 C) 11.16 E) 0.260 A) 2.84 ) Determine the [OH"] concentration in a 0.169 M solution of the strong base Ba(OH): B) 5.92x 10 MC)0.338 M D) 2.96x 101 M E) 0.298 M A) 0.169 M 10) Calculate the pOH of a solution that contains 3.50x 103 M H,O" at 25°C. A)-2.46 10) E) 2.46 C) 16.5 B) 11.5 D) 2.86 x 1012 11) Calculate the pH of a buffer that is 0.300 M HCHO2 and 0.500 M KCHO The Ka for HCHO, is 1.8 x 10 A) 3.97 11) B) 10.03 C) 3.44 D) 3.52 E) 3.74 12) Which of the following is false? A) A buffer can be composed of a weak base and its conjugate acid. B) A buffer can be composed of a weak acid and its conjugate base. C) Buffered systems are resistant to changes in pH from the addition of acid or base. D) The lower the concentration of weak acid and conjugate base, the higher the buffer capacity. E) The buffer range of an acidic buffer is the weak acid's pk 1. 12) 13) A 1.00 L buffer solution is composed of 0.250 M HF and 0.250 M NaF. Calculate the pH of the solution after the addition of 0.100 moles of gaseous HCl. Assume no volume change upon the addition of HCl. The K, for HF is 3.5 x 10 A) 3.08 13) C) 3.82 B) 3.46 D) 10.18 E) 0.37 14) A sample of N(CH3); is titrated with HBr. Determine the pH of the solution at the equivalence point. 14) C) 7 B)>7 D)<7 A) 16 E)-2

Answer 1

Q6. Correct answer is : (E) If Q > K, it means the reverse reaction will proceed (to the left) to form more reactants.

Q7. Correct answer is : (D) increasing the volume (decreasing the pressure)

Q8. Correct answer is : (A) 2.84

Q9. Correct answer is : (C) 0.338 M

Q10. Correct answer is : (B) 11.5

Q11. Correct answer is : (A) 3.97

Q12. Correct answer is : (D) The lower the concentration of weak acid and conjugate base, the higher the buffer capacity.

Q13. Correct answer is : (A) 3.08

Q14. Correct answer is : (D) <7