Question

In a first order reaction the log [reactant] versus time plot was a straight line with a negative slope of ~0.50×10^4 sec^-1 find the rate constant and half life period of reaction​

Answer 1

Answer:

Explanation:

negative rate

Answer 2

Answer:

Factors That Affect Reaction Rates

Half-lives

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A first-order reaction is a reaction that proceeds at a rate that depends linearly on only one reactant concentration.

The Differential Representation

Differential rate laws are generally used to describe what is occurring on a molecular level during a reaction, whereas integrated rate laws are used for determining the reaction order and the value of the rate constant from experimental measurements. The differential equation describing first-order kinetics is given below:

Rate=−d[A]dt=k[A]1=k[A](1)(1)Rate=−d[A]dt=k[A]1=k[A]

The "rate" is the reaction rate (in units of molar/time) and kk is the reaction rate coefficient (in units of 1/time). However, the units of kk vary for non-first-order reactions. These differential equations are separable, which simplifies the solutions as demonstrated below.

The Integral Representation

First, write the differential form of the rate law.

Rate=−d[A]dt=k[A](2)(2)Rate=−d[A]dt=k[A]

Rearrange to give:

d[A][A]=−kdt(3)(3)d[A][A]=−kdt

Second, integrate both sides of the equation.

∫[A][A]od[A][A]=−∫ttokdt(4)(4)∫[A]o[A]d[A][A]=−∫totkdt

∫[A][A]o1[A]d[A]=−∫ttokdt(5)(5)∫[A]o[A]1[A]d[A]=−∫totkdt

Recall from calculus that: