Question

The partial pressure of CH₃OH_(g) , CO_(g) and H_2(g) in equilibrium mixture for the reaction ;

CO_(g) + 2H_2(g) CH₃OH_(g) are 2.0, 1.0 and 0.1 atm respectively at 427°C. The value of K_p for decomposition of CH₃OH to CO and H₂ is –

• A. 10²atm
• B. 2 × 10²atm^–1
• C. 50 atm²
• D. 5 × 10^–3 atm²

Answer 1

Answer: (D)

5 × 10^–3 atm²

Answer 2

CO_(g) + 2H_2(g) CH₃OH_(g)

Kp = $\frac { \mathrm { P } _ { \mathrm { CH } _ { 3 } \mathrm { OH } } } { \mathrm { P } _ { \mathrm { CO } } \times \left( \mathrm { P } _ { \mathrm { H } _ { 2 } } \right) ^ { 2 } } = \frac { 2 } { 1 \times ( 0.1 ) ^ { 2 } } = 200$

Thus Kp for decomposition of CH₃OH

$= \frac { 1 } { \mathrm { Kp } } = \frac { 1 } { 200 } = 5 \times 10 ^ { - 3 } \mathrm {~atm} ^ { 2 }$