Question

In the reaction, $2A \rightarrow $ Product, the concentration of A decreases from $7.0 \,mole/ litre$ to $6.0\, mole/litre$ in $5 $ minutes. The rate of reaction is

• A. $1.0\, mol \,L ^{-1} min ^{-1}$
• B. $ 0.05\, mol \,L ^{-1} min ^{-1}$
• C. $ 0.2\, mol\, L ^{-1} min ^{-1}$
• D. $ 0.1 \, mol\,L ^{-1} min ^{-1}$

Answer 1

Answer: (D)

Rate $ =-\frac{1}{2} \frac{d[A]}{d t}$
$ =-\frac{1}{2} \frac{(7-6)}{5}=-0.1 \,mol\, L ^{-1} \min ^{-1} $
Negative sign signifies the decrease in concentration