Question

For a chemical reaction starting with some initial concentration of reactant A_t as a function of time (t) is given by the equation,

`1/("A"_"t"^4) = 2 + 1.5 xx 10^-3` t

The rate of disappearance of [A] is ____ × 10^-2 M/sec when [A] = 2 M.

[Given: [A_t] in M and t in sec.]
[Express your answer in terms of 10^-2 M /s]
[Round off your answer if required]

Options

• 1.3

• 1.2

• 5.3

• 0.5

Answer 1

The rate of disappearance of [A] is 1.2 × 10^-2 M/sec when [A] = 2 M.

Explanation:

`1/("A"_"t"^4) = 2 + 1.5 xx 10^-3` t

`therefore (-4)/(["A"]_"t"^5) ("d"["A"])/"dt" = 1.5 xx 10^-3`

`therefore - ("d"["A"])/"dt" = (1.5 xx ["A"]_"t"^5 xx 10^-3)/4`

= 1.5 × 8 × 10^-3

= 1.2 × 10^-2 m/s