What is rate constant?

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Rate Constant:

The rate constant (k) is a proportionality constant that relates the rate of a chemical reaction to the concentrations of the reactants.

It is defined as the rate of reaction when the concentrations of all reactants are 1 M.
The rate constant depends on the nature of the reaction, the temperature, and the presence of catalysts.

Units of Rate Constant:

The units of the rate constant depend on the order of the reaction.

For a first-order reaction, the units of k are s^-1 (or reciprocal seconds).
For a second-order reaction, the units of k are M^-1s^-1 (or inverse molarity seconds).
For a third-order reaction, the units of k are M^-2s^-1 (or inverse molarity squared seconds).

The units of k for higher-order reactions can be obtained by generalizing this pattern.

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CBSE CLASS XII Related Questions

1.
Give structures of A, B and C: Aniline $\xrightarrow{Br_2/H_2O}$ A $\xrightarrow{NaNO_2+HCl, 0-5^\circ C}$ B $\xrightarrow{H_3PO_2+H_2O}$ C

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2.
Why is o-nitrophenol more acidic than o-methoxyphenol?

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3.
Vitamin $B_{12}$ is a complex compound of :

$Fe^{2+}$
$Mg^{2+}$
$Co^{3+}$
$Cu^{2+}$

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4.
On hydrolysis, which of the following carbohydrates gives only $\mathrm{\beta}$-glucose ?

Starch
Sucrose
Maltose
Cellulose

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5.
Though chlorine shows strong $-I$ effect, why is it ortho/para directing?

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6.
For decomposition of $H_2O_2$ by $I^-$: Step I: $H_2O_2 + I^- \rightarrow H_2O + IO^-$ (slow). Step II: $H_2O_2 + IO^- \rightarrow H_2O + I^- + O_2$ (fast). (a) Write rate law. (b) Determine order w.r.t. $H_2O_2$ and $I^-$ and overall order. (c) Molecularity of Step II.

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What is rate constant?

CBSE CLASS XII Related Questions

1.
Give structures of A, B and C: Aniline $\xrightarrow{Br_2/H_2O}$ A $\xrightarrow{NaNO_2+HCl, 0-5^\circ C}$ B $\xrightarrow{H_3PO_2+H_2O}$ C

2.
Why is o-nitrophenol more acidic than o-methoxyphenol?

3.
Vitamin $B_{12}$ is a complex compound of :

4.
On hydrolysis, which of the following carbohydrates gives only $\mathrm{\beta}$-glucose ?

5.
Though chlorine shows strong $-I$ effect, why is it ortho/para directing?

6.
For decomposition of $H_2O_2$ by $I^-$: Step I: $H_2O_2 + I^- \rightarrow H_2O + IO^-$ (slow). Step II: $H_2O_2 + IO^- \rightarrow H_2O + I^- + O_2$ (fast). (a) Write rate law. (b) Determine order w.r.t. $H_2O_2$ and $I^-$ and overall order. (c) Molecularity of Step II.

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What is rate constant?

CBSE CLASS XII Related Questions

1.Give structures of A, B and C: Aniline $\xrightarrow{Br_2/H_2O}$ A $\xrightarrow{NaNO_2+HCl, 0-5^\circ C}$ B $\xrightarrow{H_3PO_2+H_2O}$ C

2.Why is o-nitrophenol more acidic than o-methoxyphenol?

3.Vitamin $B_{12}$ is a complex compound of :

4.On hydrolysis, which of the following carbohydrates gives only $\mathrm{\beta}$-glucose ?

5.Though chlorine shows strong $-I$ effect, why is it ortho/para directing?

6.For decomposition of $H_2O_2$ by $I^-$: Step I: $H_2O_2 + I^- \rightarrow H_2O + IO^-$ (slow). Step II: $H_2O_2 + IO^- \rightarrow H_2O + I^- + O_2$ (fast). (a) Write rate law. (b) Determine order w.r.t. $H_2O_2$ and $I^-$ and overall order. (c) Molecularity of Step II.

Comments

SUBSCRIBE TO OUR NEWS LETTER

1.
Give structures of A, B and C: Aniline $\xrightarrow{Br_2/H_2O}$ A $\xrightarrow{NaNO_2+HCl, 0-5^\circ C}$ B $\xrightarrow{H_3PO_2+H_2O}$ C

2.
Why is o-nitrophenol more acidic than o-methoxyphenol?

3.
Vitamin $B_{12}$ is a complex compound of :

4.
On hydrolysis, which of the following carbohydrates gives only $\mathrm{\beta}$-glucose ?

5.
Though chlorine shows strong $-I$ effect, why is it ortho/para directing?

6.
For decomposition of $H_2O_2$ by $I^-$: Step I: $H_2O_2 + I^- \rightarrow H_2O + IO^-$ (slow). Step II: $H_2O_2 + IO^- \rightarrow H_2O + I^- + O_2$ (fast). (a) Write rate law. (b) Determine order w.r.t. $H_2O_2$ and $I^-$ and overall order. (c) Molecularity of Step II.