Question

For a reaction A 2B, rate of disappearance of 'A' related to the rate of appearance of 'B' by the expression.

• A. $- \frac{d\lbrack A\rbrack}{dt} = \frac{1}{4}\frac{d\lbrack B\rbrack}{dt}$
• B. $- \frac{d\lbrack A\rbrack}{dt} = \frac{d\lbrack B\rbrack}{dt}$
• C. $- \frac{d\lbrack A\rbrack}{dt} = 4\frac{d\lbrack B\rbrack}{dt}$
• D. $- \frac{d\lbrack A\rbrack}{dt} = \frac{1}{2}\frac{d\lbrack B\rbrack}{dt}$

Answer 1

Answer: (A)

$- \frac{d\lbrack A\rbrack}{dt} = \frac{1}{4}\frac{d\lbrack B\rbrack}{dt}$

Answer 2

$\frac{1}{2}A\overset{\quad\quad}{\rightarrow}2B$

$- \frac{1}{1/2}\frac{d(A)}{dt} = \frac{1}{2}\frac{d(B)}{dt}$

$- \frac { \mathrm { d } ( \mathrm { A } ) } { \mathrm { dt } } = \frac { 1 } { 4 } \frac { \mathrm { d } ( \mathrm { B } ) } { \mathrm { dt } }$