The half-life of the two samples is 0.1 and 0.4 seconds, respectively. Their concentrations are 200 and 50, respectively. The order of the reactions will be:

1. 0

2. 2

3. 1

4. 4

The rate constant for a first order reaction is $4.606\times {10}^{-3}<mspace\; width="1em"></mspace>s^{-1}$. The time required to reduce 2.0 g of the reactant to 0.2 g is:

An increase in the concentration of the reactants of a reaction leads to a change in:

Consider the plots, given below, for the types of reaction

nA$\to$B+C

These plots respectively correspond to the reaction orders:

1. 0, 1, 2

2. 1, 2, 0

3. 1, 0, 2

4. None of the above

For a reaction $\frac{1}{2}A\to 2B$, rate of disappearance of 'A' is related to the rate of appearance of 'B' by the expression:

1. $-\frac{d\left[A\right]}{dt}=4\frac{d\left[B\right]}{dt}$

2. $-\frac{d\left[A\right]}{dt}=\frac{1}{2}\frac{d\left[B\right]}{dt}$

3. $-\frac{d\left[A\right]}{dt}=\frac{1}{4}\frac{d\left[B\right]}{dt}$

4. $-\frac{d\left[A\right]}{dt}=\frac{d\left[B\right]}{dt}$

For a first-order reaction $A\to P$, rate constant (k) [dependent on temperature (T)] was found
to follow the equation \(log \ k \ = \ (-2000)\frac{1}{T} \ + \ 6.0\). The pre-exponential factor A and
the activation energy $E_a$, respectively, are:

1. $1.0\times {10}^6$ $s^{-1}$ $and$ $9.2$ $kJ$ $mo{l}^{-1}$

2. $6.0$ $s^{-1}$ $and$ $16.6$ $kJ$ $mo{l}^{-1}$

3. $1.0\times {10}^6$ $s^{-1}$ $and$ $16.6$ $kJ$ $mo{l}^{-1}$

4. $1.0\times {10}^6$ $s^{-1}$ $and$ $38.3$ $kJ$ $mo{l}^{-1}$

Plots showing the variation of the rate constant (K) with temperature (T) are given below. The plot that follows Arrhenius equation is:

1.   

2.  

3.   

4.  

The time for half-life period of a certain reaction A$\to$Products is 1 hour. When the initial concentration of the reactant 'A', is 2.0 mol $L^{-1}$, how much time does it take for its concentration to change from 0.50 to 0.25 mol $L^{-1}$ if it is a zero-order reaction?

1. 1 h

2. 4 h

3. 0.5 h

4. 0.25 h

The radionuclide ${}_{90}{}^{234}Th$ undergoes two successive $\beta$-decays followed by one $\alpha$-decay. the atomic number and the mass number respectively of the resulting radionucleide are:

(1) 92 and 234

(2) 94 and 230

(3) 90 and 230

(4) 92 and 230

A radioactive element has a half-life of 20 minute. How much time should elapse before the element is reduced to 1/8 its original value?

(1) 40 minute

(2) 60 minute

(3) 80 minute

(4) 160 minute