Half-life of radioactive substance is 4 days . Amount of the substance decayed in two days is :
1 -
20 %
Assertion : The kinetics of the reaction
mA + nB + pC → m'X + n'Y + p'Z
obeys the reaction as- = k[A]m[B]n
Reason : The rate of reaction does not depend upon the concentration of C.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
For reaction aA → xP, when [A] = 2.2 mM, the rate was found to be 2.4 mM s-1. On reducing concentration of A to half, the rate changes to 0.6 mM s-1. The order of reaction with respect to A is
1.5
2.0
2.5
3.0
Assertion : According to transition state theory, for the formation of an activated complex, one of the vibrational degrees of freedom is converted into a translational degree of freedom.
Reason: Energy of the activated complex is higher than the energy of reactant molecules.
If both assertion and reason are true and reason is the correct explanation of the assertion.
If both assertion and reason are true but reason is not the correct explanation of the assertion.
If assertion is true, but reason is false.
Both assertion and reason are false statements.
A.
If both assertion and reason are true and reason is the correct explanation of the assertion.
The activated complex can also be treated as a distinct chemical species in equilibrium with the reactants which then decompose into products. It is, however, a special molecule in which one vibrational degree of freedom has been converted to a translational degree of freedom along the reaction coordinate. It must be remembered that the activated complex is not merely an intermediate in process of breaking or forming of chemical bonds. It is unstable because it is situated the maximum ofthe potential energy barrier separating the produts from the reactants. The difference between the energy of the activated complex (E1) and the energy oft he reactants (E2) is the activation energy, Ea.
E1-E2=Ea, E1>> E2.
87.5% decomposition of a radioactive substance complete in 3 hours. What is the half-life of that substance ?
2 hours
3 hours
90 minutes
1 hour
According to Hess's law, the heat of reaction depends upon :
initial condition of reactants
initial and final conditions of reactants
intermediate path of the reaction
end conditions of reactants
A reaction is catalysed by 'X' Here 'X' :
decreases the rate constant of reaction
does not affect the equilibrium constant of reaction
decreases the enthalpy of reaction
decreases the activation energy