Question

1.)Describe the effect of increasing the concentration of the reactants on the rate of a reaction.

2.)The exponents in a rate law have no relationship to the coefficients in the overall balanced equation for the reaction. Give an example of a balanced equation and the rate law for a reaction that clearly demonstrates this.

3.)Compare the half-life equations for a first-order and a second-order reaction. For which reaction order is the value of the half-life independent of the reactant concentration??

Answer 1

1) WITH THE INCREASING THE CONCNTRATION OF THE REACTANT ,THE RATE OF THE REACTION IS ALSO INCREASES.BECAUSE THE INCRESING THE CONCNTRATION OF THE REACTANT ,AMOUNT OF REACTANTA PARTICIPATE IN THAE REACTION IS ALSO INCREASES,CONSEQUENTLY THE CHANGE IN CONCENTRATION OF REACTANT IS MORE .AS RESULT THE RATE OF THE REACTION IS ALSO INCREASES

RATE OF THE REACTOION = CHANGE IN THE CONCENTRATION OFF THE REACTANT /CHANGE IN TIME

2)

The exponents in a rate law have no relationship to the coefficients in the overall balanced equation for the reaction.

FOR EXAMPLE

H2 + Br2 ------------------------> 2 HBr

theritically

rate of the reaction = k [H2]^1[Br2]^1

experimnta actually shows that rate law for the reaction of hydrogen with bromine is

rate of the reaction = k[H2]^1[Br2]^1/2

therefore the rate of the reaction does not dependa on the stoicheometric coeffcients of the reaction .it is always detemine from the mechanism of the reaction

3)

for first order ,the half life equation is

t_1/2= 0.693/K₁

FOR SECOND ORDER REACTION

t_1/2= 1/K₂ *a

in first ordre k1 is the tate consatnt for the reactionis always constant.henec the half life is independent of the concentration of the reactant.

where as in the second order the half life is inversly propotional to the initial concentration of the reactant(a)

therfore answer is first order