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In the following reaction; xA\rightarrow yB

\log_{10}\left [ -\frac{d\left [ A \right ]}{dt} \right ]=\log_{10}\left [ \frac{d\left [ B \right ]}{dt} \right ]+0.3010

'A' and 'B' respectively can be : 

  • Option 1)

    N_2O_4 and NO_2

  • Option 2)

    C_2H_4 and C_4H_8

  • Option 3)

    C_2H_2 and C_6H_6

  • Option 4)

    n-Butane and Iso-butane

A bacterial infection in an internal wound grows as N{}'(t)=N_{o}exp(t),

where the time t is in hours. A dose of antibiotic, taken orally, needs 1 hour to reach the wound.

Once it reaches there, the bacterial population goes down as \frac{dN}{dt}=-5N^{2}.

What will be the plot of \frac{N_{o}}{N} vs. t after 1 hour ? 

  • Option 1)

  • Option 2)

  • Option 3)

  • Option 4)

From o to 1 hour =>  After 1 hour, it is given :   at t = 1 hour ,  Now, This equation is similar to the straight line equation (Y=mx+C) So, the curve will be straight line. option (3) is correct.      Option 1)Option 2)Option 3)Option 4)

For the reaction of H_{2} with I_{2}, the rate constant is 2.5\times 10^{-4}dm^{3}mol^{-1}s^{-1} at 327^{\circ}C and 1.0\; dm^{3}mol^{-1}s^{-1} at 527^{\circ}C. The activation energy for the reaction , in KJmol^{-1} is :

\left ( R=8.314\; J\; K^{-1} mol^{-1}\right )

  • Option 1)

    166

  • Option 2)

    150

  • Option 3)

     72

  • Option 4)

    59

Given                                      Option 1)Option 2)Option 3) Option 4)

Consider the given plot of enthapy of the following reaction between A and B .

A+B\rightarrow C+D

Identify the incorrect statement .

  • Option 1)

    Activation enthapy to form C is 5\:kJmol^{-1} less than that to form D.

  • Option 2)

    C is the thermodynamically stable product.

  • Option 3)

    D is kinetically stable product .

  • Option 4)

    Formation of A and B from C has highest enthaply of activation .

  Activation Energy - The minimum kinetic energy that reactants must have in order to form products. - wherein Description: E.g.: In a gas phase reaction numerous collisions take place but only a tiny proportion which has sufficient energy to cross the energy barrier leads to product formation.           EC (activation energy of C) = (20-5)kJ mol- = 15 kJ mol- ED ( activation energy of D) =...

The given plots represent the variation of the concrntration of a reactant R with time for two different reactions (i) and (ii). The respective orders of the reactions are :

  • Option 1)

     1,0

  • Option 2)

     1,1

  • Option 3)

     0,1

  • Option 4)

    0,2

 =Concentration of reactant at  time 1st  order :                                                          Zero order                  (negative) So,order are  respectively            Option 1) Option 2) Option 3) Option 4)

For a reaction scheme if the rate of formation of B is set to be zero then the concentration of B is given by:

  • Option 1)

    \left ( k_{1}-k_{2} \right )\left [A \right ]

  • Option 2)

    k_{1}k_{2} \left [A \right ]

  • Option 3)

    \left ( k_{1}+k_{2} \right )\left [A \right ]

  • Option 4)

    \left ( \frac{k_{1}}{k_{2}} \right )\left [A \right ]

   (given) [B]=?               net rate of formation of  Option 1)Option 2)Option 3)Option 4)

For the reaction 2A+B \rightarrow C, the values of initial rate at different reactant concentrations are given in the table below. The rate law for the reaction is :

[A](mol\; L^{-1}) [B](mol\; L^{-1}) \\Initial Rate\\(mol\; L^{-1}s^{-1})
0.05 0.05 0.045
0.10 0.05 0.090
0.20 0.10 0.72

 

  • Option 1)

    Rate=k[A]^{2}[B]^{2}

  • Option 2)

    Rate=k[A]^{2}[B]

  • Option 3)

    Rate=k[A][B]^{2}

     

  • Option 4)

    Rate=k[A][B]

 
Rate law 0.05 0.05 0.045 0.10 0.05 0.090 0.20 0.10 0.72                Option 1) Option 2) Option 3)   Option 4)

NO_{2} required for a reaction is produced by the decomposition of N_{2}O_{5} in CCl_{4} as per the equation, 2N_{2}O_{5}(g)\rightarrow 4NO_{2}(g)+O_{2}(g).

The initial concentration of N_{2}O_{5} is 3.00 mol L^{-1} and it is 2.75 mol L^{-1} after 30 minutes. The rate of formation of NO_{2} is:

 

  • Option 1)

    4.167\times 10^{-3}molL^{-1}min^{-1}

     

     

     

  • Option 2)

    1.667\times 10^{-2}molL^{-1}min^{-1}

  • Option 3)

    8.333\times 10^{-3}molL^{-1}min^{-1}

  • Option 4)

    2.083\times 10^{-3}molL^{-1}min^{-1}

 
()                   so,  from the reaction    Option 1)       Option 2) Option 3) Option 4)
how to find slowest reaction in chemical kinetic
The reaction mechanism is the step-by-step process by which reactants actually become products. The overall reaction rate depends entirely on the rate of the slowest step. If the first step is the slowest, entire reaction must wait for it, then it is the rate-determining step.
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The time required to reduce concentration of NO can be calculated as:

K reprsent the rate of reaction when log K is ploted against 1/T the graph is obtain as

Let us understand this question with the help of a graph plotted between log K and 1/T

The rate of a reaction A doubles on increasing the temperature from 300 to 310 K.  By how much, the temperature 

  • Option 1)

    9.84 K

  • Option 2)

     4.92 K

  • Option 3)

     2.45 K

  • Option 4)

    19.67 K

     

 
Option 1) 9.84 K Option 2)  4.92 K Option 3)  2.45 K Option 4) 19.67 K  

A reaction having equal energies of activation for forward and reverse reactions has:

  • Option 1)

    \DeltaH = \DeltaG = \DeltaS=0

  • Option 2)

    \DeltaS = 0

  • Option 3)

    \DeltaG = 0

  • Option 4)

    \DeltaH = 0

 
Option 1) H = G = S=0 Option 2) S = 0 Option 3) G = 0 Option 4) H = 0

If a reaction follows the Arrhenius equation , the plot Ink vs \frac{1}{(RT)} gives straight line with a gradient  (-y) unit . The energy required to activate the reactant is:

  • Option 1)

    -y unit 

  • Option 2)

    y/R unit 

  • Option 3)

    y unit 

  • Option 4)

    yR unit 

  Arrhenius Parameters - The pre-exponential factor/ frequency factor (A) and activation energy () are called Arrhenius parameters. - wherein Formula: A = Pre-exponential factor  = Activation Energy       Arrhenius Equation - Arrhenius gave the quantitative dependence of rate constant on temperature by the Arrhenius equation. - wherein = Rate constant aas we know that Arrhenius equation...

The reaction 2X \rightarrow B is a zeroth order reaction. If the initial concentration of X is 0.2 M , the half- life is 6 h. When the initial concentration of X is 0.5 M, the time required to reach its final concentration of 0.2 M will be :

  • Option 1)

    7.2 h

  • Option 2)

    9.0 h

  • Option 3)

    18.0 h

  • Option 4)

    12.0 h

3

For a reaction, consider the plot of In k versus 1/T given in the figure. If the rate constant of this reaction at 400 K is 10-5 s-1 , then the rate constant at 500 K is :

  • Option 1)

    10^{-6}\: s^{-1}

  • Option 2)

    2 \times 10^{-4}\: s^{-1}

  • Option 3)

    10^{-4}\: s^{-1}

  • Option 4)

    4 \times10^{-4}\: s^{-1}

  Chemical Kinetics - The branch of chemistry which predicts the rate and mechanism of a process -     Effect of Temperature and Activation Energy on rate constant -                                   decreases with the increase in T                   increases with increase in T  = Activation Energy T = Temperature   = Rate constant - wherein       Rate of reaction - The  rate of the reaction...

For an elementry chemical reationA_{2}\xrightarrow[k_{-1}]{k_{1}}2A the expression for\frac{d\left [ A \right ]}{dt}  is:

 

  • Option 1)

    2k_{1}\left [ A_{2} \right ]-2k_{-1}\left [ A \right ]^{2}

  • Option 2)

    k_{1}\left [ A_{2} \right ]+2k_{-1}\left [ A \right ]^{2}

  • Option 3)

    2k_{1}\left [ A_{2} \right ]-k_{-1}\left [ A \right ]^{2}

  • Option 4)

    k_{1}\left [ A_{2} \right ]-k_{-1}\left [ A \right ]^{2}

  Rates in presence of stoichiometry of reactants/products - When stoichiometry coefficients of reactants/ products are not equal to one, the rate of disappearance of  & the rate of appearance of products is divided by their respective stoichiometric coefficients - wherein    Option 1)Option 2)Option 3)Option 4)

Consider the given plots for a reaction obeying Arrhenius equation ( 0^{0}C\: < \: T\: <\: 300^{0}C ) : (k and E_{a} are rate constant and activation energy , respectively )

  • Option 1)

    I is right but II is wrong .

  • Option 2)

    Both I and II are correct.

  • Option 3)

    I is wrong but II is right .

  • Option 4)

    Both I and II are wrong

  Arrhenius Equation - Arrhenius gave the quantitative dependence of rate constant on temperature by the Arrhenius equation. - wherein = Rate constant as we have learned in Arrhenius equation when we increase Ea, K should decrease    Option 1)I is right but II is wrong .Option 2)Both I and II are correct.Option 3)I is wrong but II is right .Option 4)Both I and II are wrong

Decomposition of X exhibits a rate constant of 0.05 \mu g/year. How many years are required for the decomposition of 5 \mu g of X into 2.5 \mu g ?

  • Option 1)

    25

  • Option 2)

    40

  • Option 3)

    20

  • Option 4)

    50

  Rate Determining Step - The overall rate of reaction is controlled by the slowest step in a reaction called the rate determining step. - wherein e.g. As wehave learned in zero order reaction unit of rate constant it is zero order reaction then half life of the reaction will be  Option 1)25Option 2)40Option 3)20Option 4)50

For the reaction , 2A + B \rightarrow products , when the concentrations of A and B both were doubled , the rate of the reaction increased from 0.3\: mol\: L^{-1}s^{-1}\: to\:2.4 \: mol\: L^{-1}s^{-1} . When the concentration of A alone is doubled , the rate increased from 0.3\: mol\: L^{-1}s^{-1}\: to\:0.6 \: mol\: L^{-1}s^{-1}.

Which one of the following statement is correct ?

 

  • Option 1)

    Order of the reaction with respect to B is 1 

  • Option 2)

    Order of reaction with respect to A is 2

  • Option 3)

    Total order of the reaction is 4

  • Option 4)

    Order of the reaction with respect to B is 2

  Zero Order Reaction - Zero order reaction means that the rate of the reaction is proportional to zeroth power of the concentration of reactants   - wherein  time required for half completion of reaction     nth order reaction - The rates of the reaction is proportional to nth power of reactant - wherein Differential rate law Integrated rate laws, a= initial, concentration of reactant at...
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