Calculate the half-life of the first-order reaction C2H4O(g) arrow (CH)4(g)+CO(g) if the initial pressure of C2H4O(g) is 80mm and the total pressure at the end of 20 minutes is 120mm

Question

Calculate the half-life of the first-order reaction C2H4O(g) arrow (CH)4(g)+CO(g) if the initial pressure of C2H4O(g) is 80mm and the total pressure at the end of 20 minutes is 120mm (A) 40min (B) 120min (C) 20min (D) 80min

Tardigrade Admin · Accepted Answer

C2H4O(g) arrow (CH)4(g)+CO(g) Initially 80 mm 0 0 After 20 minutes 80-y y y Total pressure = 80-y +y+y = 80 + y = 120 y = 40 50% of reactant decomposed within 20 minutes, so half life will be 20 minutes.

Q. Calculate the half-life of the first-order reaction
$C_{2} H_{4} O (g) \to (C H)_{4} (g) + CO (g)$
if the initial pressure of $C_{2} H_{4} O (g)$ is $80 mm$ and the total pressure at the end of $20$ minutes is $120 mm$

$40 min$

$120 min$

$20 min$

$80 min$

$C_{2} H_{4} O (g) \to (C H)_{4} (g) + CO (g)$
Initially 80 mm 0 0
After 20 minutes 80-y y y
Total pressure = 80-y +y+y = 80 + y = 120
y = 40
50% of reactant decomposed within 20 minutes, so half life will be 20 minutes.

Q. Calculate the half-life of the first-order reaction C2​H4​O(g)→(CH)4​(g)+CO(g) if the initial pressure of C2​H4​O(g) is 80mm and the total pressure at the end of 20 minutes is 120mm

40min

120min

20min

80min