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When a biochemical reaction is carried out in a laboratory outside the human body in the absence of an enzyme, then the rate of reaction obtained is $10^{-6}$ times. The activation energy of a reaction in the presence of an enzyme is:

Which one of the following statements is incorrect related to Molecular Orbital Theory?

The temperature dependence of the rate constant ($k$) of a chemical reaction is written in terms of the Arrhenius equation, $k = A e^{-E^*/RT}$. The activation energy ($E^*$) of the reaction can be calculated by plotting:

Given the following five species: $NH_3, AlCl_3, BeCl_2, CCl_4, PCl_5$. The total number of these species that do not have eight electrons around the central atom in its/their outermost shell, is:

A steady current of 1.5 A flows through a copper voltmeter for 10 min. If the electrochemical equivalent of copper is $30 \times 10^{-5} \text{ g C}^{-1}$, the mass of copper deposited on the electrode will be:

The half-life of a first-order reaction is $2000 \text{ years}$. If the concentration after $8000 \text{ years}$ is $0.02 \text{ M}$, then the initial concentration was:

For a reaction $3A \rightarrow 2B$, the average rate of appearance of B is given by $\frac{\Delta [B]}{\Delta t}$. The correct relation between the average rate of appearance of B with the average rate of disappearance of A is:

For the reaction, $2A + B \rightarrow 3C + D$, which of the following is an incorrect expression for the rate of reaction?

Which of the following molecules acts as a Lewis acid?

Effective collisions are known to possess: A: Energy greater than the threshold energy. B: Breaking of old bonds in the reactant. C: Formation of a new bond in the product. D: High activation energy. E: Proper orientation. Choose the correct answer from the options given below:

The correct order of increasing C-X bond reactivity toward nucleophiles among the following is: I. [Missing] II. [Missing] III. $(\text{CH}_3)_3\text{C-X}$ IV. $(\text{CH}_3)_2\text{CH-X}$

Find the correct sequence of the bond enthalpy of the $\text{C-X}$ bond among the following:

$K_c$ and $K_p$ are not equal for a reaction given below:

The compound that will undergo $\text{S}_\text{N}1$ reaction with the fastest rate is:

A hydrogen gas electrode is made by dipping platinum wire in a solution of HCl of $\text{pH} = 10$ and by passing hydrogen gas around the platinum wire at one atm pressure. The oxidation potential of the electrode would be:

A physician wishes to prepare a buffer solution at $\text{pH}=3.58$ that efficiently resists changes in pH yet contains only small concentration of the buffering agents. Which one of the following weak acids together with its sodium salt would be best to use?

A device that converts energy of the combustion of fuels like hydrogen and methane, directly into electrical energy is known as:

In the electrochemical cell: $\text{Zn}|\text{ZnSO}_4(0.01 \text{ M}) || \text{CuSO}_4(1.0 \text{ M})|\text{Cu}$, the emf of this Daniel cell is $E_1$. When the concentration of $\text{ZnSO}_4$ is changed to $1.0 \text{ M}$ and that of $\text{CuSO}_4$ is changed to $0.01 \text{ M}$, the emf changes to $E_2$. The relationship between $E_1$ and $E_2$ is : (Given, $\frac{RT}{F} = 0.059$)

A button cell used in watches functions as following: $\text{Zn}(s) + \text{Ag}_2\text{O}(s) + \text{H}_2\text{O}(l) \rightleftharpoons 2\text{Ag}(s) + \text{Zn}^{2+}(aq) + 2\text{OH}^-(aq)$ If half-cell potentials are: $\text{Zn}^{2+}(aq) + 2e^- \rightarrow \text{Zn}(s) \quad E^\circ = -0.76 \text{ V}$ $\text{Ag}_2\text{O}(s) + \text{H}_2\text{O}(l) + 2e^- \rightarrow 2\text{Ag}(s) + 2\text{OH}^-(aq) \quad E^\circ = 0.34 \text{ V}$ The cell potential will be:

The fertilizer which makes the soil acidic is: