Supplemental
1. Consider the reaction: N (g)+3H (g) 2NH (g) 22 3 . If the standard
molar free energy of formation of NH3(g) at 298 K is – 16.45 kJ
mol-1
, calculate the equilibrium constant for this reaction at 298 K.
(a) 3.62 x 10-2 ; (b) 1.66 x 10-3 ; (c) 5.26 x 10-14 ; (d) 1.71 x 10-6 ;
(e) 2.29 x 10-7
. Correct answer: d.
2. The pH of 0.1 M CH3COOH is 2.87. What is the value of KA for
CH3COOH? (a) 1.3 x 10-3 ; (b) 1.8 x 10-6 ;(c) 1.8 x 10-5 ; (d) 0.037;
(e) 2.7 x 10-6
. Correct answer: c.
3. The conjugate base of HSO4
- is: (a) OH- ; (b) SO4
2- ; (c) H2SO4; (d)
HSO4
- (e) H2O. Correct answer: b.