The half life of a substance in a certain enzymecatalysed reaction is 138 s. The time required for the concentration of the substance to fall from 1.28 mg L-1 to 0.04 mg L-1, is -

Question

The half life of a substance in a certain enzymecatalysed reaction is 138 s. The time required for the concentration of the substance to fall from 1.28 mg L-1 to 0.04 mg L-1, is - (A) 276 s (B) 414 s (C) 552 s (D) 690 s

Tardigrade Admin · Accepted Answer

1.28 â 0.64 â 0.32 â 0.16 â 0.08 â 0.04 No. of half lifes (n) = 5 5 = (Total times/138) = 5 × 138 time required = 690 s

Q. The half life of a substance in a certain enzymecatalysed reaction is 138 s. The time required for the concentration of the substance to fall from $1.28 m g L^{- 1}$ to $0.04 m g L^{- 1}$ , is -

276 s

414 s

552 s

690 s

1.28 → 0.64 → 0.32 → 0.16 → 0.08 → 0.04
No. of half lifes (n) = 5
$5 = \frac{T o t a l t im es}{138}$
$= 5 \times 138$
time required $= 690 s$

Q. The half life of a substance in a certain enzymecatalysed reaction is 138 s. The time required for the concentration of the substance to fall from 1.28mgL−1 to 0.04mgL−1, is -