Read the passage carefully and answer the Questions.
The decomposition of $N_2O_5 (g)$ is given as
$N_2Os (g) → 2NO_2(g) +\frac{1}{2}O_2(g)$
The above reaction is found to be of first order.
Predict the intercept for the plot of $\log\frac{[N_2O_5]_o}{[N_2O_5]}$ versus time
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → zero
The intercept for the plot of log([N₂O₅]₀ / [N₂O₅]) versus time is zero.
For a first-order reaction:
log([A]₀ / [A]) = (k / 2.303) t
Comparing with the straight-line equation:
y = mx + c
So,
y = log([N₂O₅]₀ / [N₂O₅])
x = t
m = k / 2.303
c = intercept
At time t = 0:
[N₂O₅] = [N₂O₅]₀
Substituting:
log([N₂O₅]₀ / [N₂O₅]₀) = log(1) = 0
When t = 0, y = 0
Therefore,
Intercept (c) = 0
Hence, zero is the answer