For the reaction, A ⇌ B, Ea = 50 kJ mol−1 and ΔH = −20 kJ mol−1. When a catalyst is added, Ea decreases by 10 kJ mol−1. What is the Ea for the backward reaction in the presence of catalyst?
Show Hint
- 60 kJ mol−1
- 40 kJ mol−1
- 70 kJ mol−1
- 20 kJ mol−1
The Correct Option is A
Solution and Explanation
Top Questions on Thermodynamics
- Two gases A and B are filled at the same pressure in separate cylinders with movable pistons of radii \(r_A\) and \(r_B\) respectively. On supplying an equal amount of heat to both the cylinders, their pressures remain constant and their pistons are displaced by 16 cm and 9 cm respectively. If the change in their internal energies is the same, then the ratio \(r_A / r_B\) is:
- NEET (UG) - 2025
- Physics
- Thermodynamics
- A gas is compressed from an initial volume of 10 L to 5 L. The pressure during the compression is constant at 2 atm. Calculate the work done on the gas.
- MHT CET - 2025
- Chemistry
- Thermodynamics
- 500 J of energy is transferred as heat to 0.5 mol of Argon gas at 298 K and 1.00 atm. The final temperature and the change in internal energy respectively are: Given \( R = 8.3 \, \text{J K}^{-1} \text{mol}^{-1} \).
- JEE Main - 2025
- Chemistry
- Thermodynamics
- Given below is the plot of the molar conductivity vs \( \sqrt{c} \) concentration for KCl in aqueous solution. If, for the higher concentration of KCl solution, the resistance of the conductivity cell is 100 \( \Omega \), then the resistance of the same cell with the dilute solution is 'x' \( \Omega \). The value of \( x \) is:
- JEE Main - 2025
- Chemistry
- Thermodynamics
For a given reaction \( R \rightarrow P \), \( t_{1/2} \) is related to \([A_0]\) as given in the table. Given: \( \log 2 = 0.30 \). Which of the following is true?
\([A]\) (mol/L) \(t_{1/2}\) (min) 0.100 200 0.025 100 A. The order of the reaction is \( \frac{1}{2} \).
B. If \( [A_0] \) is 1 M, then \( t_{1/2} \) is \( 200/\sqrt{10} \) min.
C. The order of the reaction changes to 1 if the concentration of reactant changes from 0.100 M to 0.500 M.
D. \( t_{1/2} \) is 800 min for \( [A_0] = 1.6 \) M.- JEE Main - 2025
- Chemistry
- Thermodynamics
Questions Asked in KCET exam
A wooden block of mass M lies on a rough floor. Another wooden block of the same mass is hanging from the point O through strings as shown in the figure. To achieve equilibrium, the coefficient of static friction between the block on the floor and the floor itself is
- KCET - 2025
- Newtons Laws of Motion
The circuit shown in the figure contains two ideal diodes \( D_1 \) and \( D_2 \). If a cell of emf 3V and negligible internal resistance is connected as shown, then the current through \( 70 \, \Omega \) resistance (in amperes) is:
- KCET - 2025
- Refractive index
- If \(N_2\) gas is bubbled through water at 293 K, how many moles of \(N_2\) gas would dissolve in 1 litre of water? Assume that \(N_2\) exerts a partial pressure of 0.987 bar. [Given \(K_H\) for \(N_2\) at 293 K is 76.48 K bar]
- KCET - 2025
- Gas laws
Among the following, identify the compound that is not an isomer of hexane:
- KCET - 2025
- Organic Chemistry
- A series LCR circuit containing an AC source of 100V has an inductor and a capacitor of reactances 24\(\Omega\) and 16\(\Omega\) respectively. If a resistance of 6\(\Omega\) is connected in series, then the potential difference across the series combination of inductor and capacitor will be
- KCET - 2025
- Electromagnetic waves