Using your understanding of conjugate acids and bases pick the correct statement from the multiple choices. a) hcnh+ is the conjugate base of hcn. b) nh2- is the conjugate acid of nh3. c) hpo42- is the conjugate base of hpo42-. d) so42- is the conjugate base of h2so4. e) haso32- is the conjugate acid of aso33-.

Option (e) is correct

Explanation:

According to definition of acid-conjugate base or base-conjugate acid pair-

if HA is an acid then is it's conjugate base

if B is a base then is it's conjugate acid

a) HCN is an acid . So, is it's conjugate base

b) is a base. So, is it's conjugate acid

c) Conjugate base of is

d) is the conjugate base of

e) is the conjugate acid of

So, option (e) is correct

n2(g) + 3h2-> 2nh3(g)   this is the balanced equation

note the mole ratio between n2, h2 and nh3.   it is 1 : 3 : 2   this will be important.

moles n2 present = 28.0 g n2 x 1 mole n2/28 g = 1 mole n2 present

moles h2 present = 25.0 g h2 x 1 mole h2/2 g = 12.5 moles h2 present

based on mole ratio, n2 is limiting in this situation because there is more than enough h2 but not enough n2.

moles nh3 that can be produced = 1 mole n2 x 2 moles nh3/mole n2 = 2 moles nh3 can be produced

grams of nh3 that can be produced = 2 moles nh3 x 17 g/mole = 34 grams of nh3 can be produced

note:   the key to this problem is recognizing that n2 is limiting, and therefore limits how much nh3 can be produced.