Question

A graph plotted between log k vs 1/T for calculating activation energy is shown by

Answer 1

The correct option is ( b ).

To understand this graph properly, we must know the Arrhenius gas equation, which is,

K= Ae^-(Ea/RT).

All the terms hold their respective regular meaning. Then by taking log on both sides and solving further, we obtain the slope as, -Ea /2.303R or simply -Ea/R. And the y - intercept is log A.

From here we conclude, that the slope is negative, which means that angle with x - axis is greater than 90° also that the point on which the straight line of graph intercepts the y - axis is log A which is positive.

Hence all the conclusions point out towards option b as it has negative slope and a positive y intercept

Thank you