A solution-phase reaction obeys the rate law

CHEMISTRY · Single correct · A Level · Chemistry · Rate equations · Rate equations

Problem

\text{rate} = k[A]^{0.5}[B]^2

. Initially,

[A] = 0.050\,\text{M}

[B] = 0.050\,\text{M}

, and

T = 298\,\text{K}

. Laboratory limits require that

[A]

not exceed

0.200\,\text{M}

[B]

not exceed

0.125\,\text{M}

, and the temperature not increase by more than

15\,^{\circ}\text{C}

. Which set of adjustments will increase the initial rate by at least a factor of 10 while staying within all limits? (A

15\,^{\circ}\text{C}

temperature rise multiplies

k

by 1.6.) (a) Increase

[B]

0.125\,\text{M}

; leave

[A]

and

T

unchanged. (b) Increase

[A]

0.200\,\text{M}

and

[B]

0.125\,\text{M}

; leave

T

unchanged. (c) Raise the temperature by

15\,^{\circ}\text{C}

; leave

[A]

and

[B]

unchanged. (d) Increase

[B]

0.100\,\text{M}

and raise

T

15\,^{\circ}\text{C}

; leave

[A]

unchanged.