List of practice Questions

If the time required for 40% completion of a first order reaction is 50 minutes, what is the time required for completion of 80% of the same reaction?
(\( \log 2 = 0.3010, \log 5 = 0.6990, \log 6 = 0.7782 \))
Given below are two statements
Assertion (A): A catalyst generally increases the rate of a reaction
Reason (R): It lowers the activation energy of a reaction by providing a new path
Which of the following correctly represents the integrated rate law equation for a first order reaction in the gas phase?
Which of the following correctly represents integrated rate law equation for a first order reaction in gas phase:
Consider the following equilibrium, $$ 2 \text{NO}(g) \rightleftharpoons \text{N}_2 (g) + \text{O}_2 (g); K_1 = 2.4 \times 10^{20} $$ $$ \text{NO}(g) + \frac{1}{2} \text{Br}_2 (g) \rightleftharpoons \text{NOBr}(g); K_2 = 1.4 $$ Calculate $ K_C $ for the reaction, $$ \frac{1}{2} \text{N}_2 (g) + \frac{1}{2} \text{O}_2 (g) + \frac{1}{2} \text{Br}_2 (g) \rightleftharpoons \text{NOBr}(g) $$
The equilibrium constants for the reactions a, b, and c are as given:
a) N$_2$ + 3H$_2$ = 2NH$_3$ : K$_1$
b) N$_2$ + O$_2$ = 2NO : K$_2$
c) 2H$_2$ + O$_2$ = 2H$_2$O : K$_3$
What would be the equilibrium constant for the reaction:
4NH$_3$ + 5O$_2$ = 4NO + 6H$_2$O; K$_x$
At T(K), the $K_p$ for the reaction $A_2B_6(g) \rightleftharpoons 2A_2B_4(g) + B_2(g)$ is 0.04 atm. The equilibrium pressure (in atm) of $A_2B_6(g)$ when it is placed in a flask at 4 atm pressure and allowed to come to above equilibrium is
One mole of \( PCl_5(g) \) was heated in a 1L closed flask at 500 K. At equilibrium, 0.1 mole of \( Cl_2(g) \) was formed. What is its \( K_p \) (in atm)? (Given R = 0.082 L atm mol\(^{-1} \) K\(^{-1} \))
One mole of \( A (g) \) is heated to \( T(K) \) till the following equilibrium is obtained \[ A(g) \rightleftharpoons B(g) \] The equilibrium constant of this reaction is \( 10^{-1} \). After reaching the equilibrium, 0.5 moles of A (g) is added and heated. The equilibrium is again established. The value of \( \left[\frac{A}{B}\right] \) is
Observe the following species \[ \text{AlCl}_3, \, \text{NH}_3, \, \text{H}^+, \, \text{Co}^{3+}, \, \text{OH}^-, \, \text{H}\text{Mg}^{2+}, \, \text{BF}_3, \, \text{Cl}^- \] How many Lewis bases are present in the above list?
Observe the following equilibrium $$\text{Fe}^{3+}(aq) + \text{SCN}^-(aq) \rightleftharpoons [\text{Fe(SCN)}]^{2+}(aq)$$ yellow \hspace{1cm colourless \hspace{1cm} deep red}
Addition of aqueous oxalic acid solution to the above equilibrium
Given below are two statements
Statement I: The changes in pH with temperature are so small that we often ignore it
Statement II: When the hydrogen ion concentration changes by a factor of 100, the pH changes by one unit
In the light of above statements, identify the correct answer from the options given below
One mole H\textsubscript{2O(g) and one mole CO(g) are taken in 1L flask and heated to 725K. At equilibrium, 40\% (by mass) of water reacted with CO(g) as follows:} \[ \text{H}_2\text{O(g)} + \text{CO(g)} \rightleftharpoons \text{H}_2\text{(g)} + \text{CO}_2\text{(g)} \] Its $K_c$ value is

At 1000 K, the value of $K_c$ for the below reaction is $10 \text{ mol L}^{-1}$. Value of $K_p$ (in atm) is (given $R = 0.082 \text{ atm L mol}^{-1} \text{K}^{-1}$)
${\{A(g) <=> B(g) + C(g)}$

At 300 K, the total pressure of the following system is 2 atm, at equilibrium: \[ \text{A}_2(g) \rightleftharpoons 2\text{A}(g) \] The atoms of A occupy 20% volume at STP. The \(K_c\) of the system is approximately (Given: R = 0.082 L atm mol\(^{-1}\) K\(^{-1}\), STP volume of 1 mole of a gas = 22.7 L)
Informal Letter :
You are Raj/Rajani Malhotra. Write a letter to your friend Rohan/Rohini appealing him/her to play 'Safe Holi'. Make use of the points given in the advertisement. You may add your own points.
Calculate the mole fraction of solute, if the vapour pressure of pure benzene at certain temperature is 640 mmHg and vapour pressure of solution of a solute in benzene is 600 mmHg.
In a $ A_xB_y $ crystal structure, $ A^{+y} $ ions occupy all the tetrahedral voids and $ B^{-x} $ ions make BCC unit cell. What is the formula of the compound?
CsCl crystallizes in a BCC structure. The radii of cation and anion are 165 pm and 182 pm respectively. What is the edge length of the unit cell?
Out of seven crystal systems, how many have face-centred unit cells?
The given unit cell belongs to the type:
The given unit cell belongs
Which of the following molecules is not aromatic?
In \( A_3B \) crystal structure, A atoms occupied all octahedral as well as all tetrahedral voids and B atoms are at FCC centres. What is the formula of compound \( A_3B \)?
Which one of the following is correct?

Which of the following reactions are not feasible?