Answer to Question #189767 in Chemistry for Michael

Question

Calculate the ΔGo (in kJ/mol) of the following reaction at 298 K. Express your answer in four significant figures and omit the unit.

N

H

3

(

g

)

+

H

C

l

(

g

)

→

N

H

4

C

l

(

s

)

Δ

G

o

f

[

N

H

3

(

g

)

]

=

−

16.48

k

J

m

o

l

Δ

G

o

f

[

H

C

l

(

g

)

]

=

−

95.30

k

J

m

o

l

Δ

G

o

f

[

N

H

4

C

l

(

s

)

]

=

−

202.9

k

J

m

o

l

Answer 1

Solution:

Balanced chemical equation:

NH₃(g) + HCl(g) → NH₄Cl(s)

ΔG^o_f[NH₃(g)] = −16.48 kJ/mol

ΔG^o_f[HCl(g)] = −95.30 kJ/mol

ΔG^o_f[NH₄Cl(s)] = −202.9 kJ/mol

ΔG^o_r = ΔG^o_f[NH₄Cl(s)] − (ΔG^o_f[NH₃(g)] + ΔG^o_f[HCl(g)])

ΔG^o_r = −202.9 kJ/mol − (−16.48 kJ/mol + (−95.30 kJ/mol)) = −91.12 kJ/mol

ΔG^o_r = −91.12 kJ/mol

Answer: ΔG^o_r = −91.12 kJ/mol