The thermal decomposition of HCOOH is a first-order reaction with a rate constant of 2-4-10-3s-1 at certain temperature- How long will it take for three-fourths of the initial quantity of HCOOH to decompose-

Time required to decompose SO₂Cl₂ to half of its initial amount is 60 minutes. If the decomposition is a first order reaction, calculate the rate constant of the reaction.

Q. The decomposition of NH3 on platinum surface is zero order reaction. If rate constant (k) is

4 \times 10^{- 3} m s^{- 1}

, how long will it take to reduce the initial concentration of

N H_{3}

from 0.1 M to 0.064 M.

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The thermal decomposition of HCOOH is a first-order reaction with a rate constant of 2.4×10−3s−1 at certain temperature. How long will it take for three-fourths of the initial quantity of HCOOH to decompose?

The correct option is A 578 secHalf-life for a first order reaction is 0.693k.t1/2=0.693k0.6932.4×10−3S−1=288.75 sect3/4=2×t1/2=577.50s=578 secHence, option A is correct.

The thermal decomposition of $H C O O H$ is a first-order reaction with a rate constant of $2.4 \times 10^{- 3} s^{- 1}$ at certain temperature. How long will it take for three-fourths of the initial quantity of $H C O O H$ to decompose?

The correct option is A $578 s e c$
Half-life for a first order reaction is $\frac{0.693}{k}$ .

$t_{1 / 2} = \frac{0.693}{k} \frac{0.693}{2.4 \times 10^{- 3} S^{- 1}} = 288.75 s e c$

$t_{3 / 4} = 2 \times t_{1 / 2} = 577.50 s = 578 s e c$

Hence, option A is correct.