Skip to main content

Two reactions are given below: 2 Fe_(s)+ 3 2 O_2(g)→ Fe_2 O_3(s),Δ H^o=-822 kJ/ mol C_(s)+ 1 2 O_2(g)→ CO_(g),Δ H^o=-110 kJ/ mol Then enthalpy change…

JEE Main 2024 — Chemistry Physical Chemistry

2024integermedium

Two reactions are given below:

2Fe(s)+32O2(g)→Fe2O3(s),ΔHo=−822kJ/mol2{\mathrm{Fe}}_{(s)}+\frac{3}{2}{O}_{2(g)}\rightarrow {\mathrm{Fe}}_{2}{O}_{3(s)},\Delta {H}^{o}=-822\mathrm{kJ}/\mathrm{mol}2Fe(s)​+23​O2(g)​→Fe2​O3(s)​,ΔHo=−822kJ/mol

C(s)+12O2(g)→CO(g),ΔHo=−110kJ/mol{C}_{(s)}+\frac{1}{2}{O}_{2(g)}\rightarrow {\mathrm{CO}}_{(g)},\Delta {H}^{o}=-110\mathrm{kJ}/\mathrm{mol}C(s)​+21​O2(g)​→CO(g)​,ΔHo=−110kJ/mol

Then enthalpy change for following reaction

3C(s)+Fe2O3(s)→2Fe(s)+3CO(g)3{C}_{(s)}+{\mathrm{Fe}}_{2}{O}_{3(s)}\rightarrow 2{\mathrm{Fe}}_{(s)}+3{\mathrm{CO}}_{(g)}3C(s)​+Fe2​O3(s)​→2Fe(s)​+3CO(g)​

Official previous-year question

Held on 30 Jan 2024 · Verified 6 Jul 2026.

Did you get this right?

Sign in to track your attempts and accuracy.

Your note

Sign in to keep a private note on this question. Nothing you write is ever public.

JEE Main Physical Chemistry in other years

More JEE Main Physical Chemistry questions

What is the ratio of wave number of first line (lowest energy line) of Balmer series of H atomic spectrum to first line of its Brackett series?

2026medium

![JEE Main 2026 Chemistry, Structure of Atom — question figure 1](https://prepforbharat.s3.ap-south-1.amazonaws.com/exam/615f0e999476412f48314daf/Chemistry/images/Structure_of_Atom/6983c1ae8bfdbb24356397c7/question_1__q_6983c1ae8bfdbb24356397c7__cdn-question-pool.getmarks.app__28S1_q_64_1__80fd8624a7_final_ppt_sync.png) ![JEE Main 2026 Chemistry, Structure of Atom — question figure 2](https://prepforbharat.s3.ap-south-1.amazonaws.com/exam/615f0e999476412f48314daf/Chemistry/images/Structure_of_Atom/6983c1ae8bfdbb24356397c7/question_2__q_6983c1ae8bfdbb24356397c7__cdn-question-pool.getmarks.app__28S1_q_64_2__04a1587871_final_ppt_sync.png) Which of the following point in Figure 2 most accurately represents the nodal surface as shown in Figure 1?

2026medium

At 298 K, the mole percentage of $\mathrm{N}_{2}(\mathrm{~g})$ in air is $80 \%$. Water is in equilibrium with air at a pressure of 10 atm. What is the mole fraction of $\mathrm{N}_{2}(\mathrm{~g})$ in water at 298 K ? ($\mathrm{K}_{\mathrm{H}}$ for $\mathrm{N}_{2}$ is $6.5 \times 10^{7} \mathrm{~mm} \mathrm{Hg}$)

2026medium

Electricity is passed through an acidic solution of $\mathrm{Cu}^{2+}$ till all the $\mathrm{Cu}^{2+}$ was exhausted, leading to the deposition of 300 mg of Cu metal. However, a current of 600 mA was continued to pass through the same solution for another 28 minutes by keeping the total volume of the solution fixed at 200 mL. The total volume of oxygen evolved at STP during the entire process is $\_\_\_\_$ mL. (Nearest integer) [Given: $\mathrm{Cu}^{2+}(\mathrm{aq})+2 \mathrm{e}^{-} \rightarrow \mathrm{Cu}(\mathrm{s}) \mathrm{E}_{\text {red }}^{\mathrm{o}}=+0.34 \mathrm{~V}$ $\mathrm{O}_{2}(\mathrm{~g})+4 \mathrm{H}^{+}+4 \mathrm{e}^{-} \rightarrow 2 \mathrm{H}_{2} \mathrm{O} \mathrm{E}_{\text {red }}^{\mathrm{o}}=+1.23 \mathrm{~V}$ Molar mass of $\mathrm{Cu}=63.54 \mathrm{~g} \mathrm{~mol}^{-1}$ Molar mass of $\mathrm{O}_{2}=32 \mathrm{~g} \mathrm{~mol}^{-1}$ Faraday Constant $=96500 \mathrm{C} \mathrm{mol}^{-1}$ Molar volume at $\mathrm{STP}=22.4 \mathrm{~L}$]

2026hard

Arrange the following resultant mixtures in increasing order of their pH values A. $10$ mL $0.2$ M Ca(OH)$_2$ + $25$ mL $0.1$ M HCl B. $10$ mL $0.01$ M H$_2$SO$_4$ + $10$ mL $0.01$ M Ca(OH)$_2$ C. $10$ mL $0.1$ M H$_2$SO$_4$ + $10$ mL $0.1$ M KOH Choose the correct answer from the options given below:

2026medium

Other Chemistry topics for JEE Main

Keep practicing Physical Chemistry

Work through every JEE Main Physical Chemistry PYQ, year by year.

Browse all Chemistry topics