Question

The magnitude of work done by a gas that undergoes a reversible expansion along the path $\mathrm{A}\mathrm{B}\mathrm{C}$ shown in the figure is _________.

JEE Main 2020 (08 Jan Shift 1)

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Question

For the reaction
${\mathrm{C}}_2{\mathrm{H}}_6\to {\mathrm{C}}_2{\mathrm{H}}_4+{\mathrm{H}}_2$
the reaction enthalpy ${∆}_{\mathrm{r}}\mathrm{H} \mathrm{in}$ ${\mathrm{kJmol}}^{-1}$ is 
(Round off to the Nearest Integer).
[Given : Bond enthalpies in ${\mathrm{kJmol}}^{-1}:\mathrm{C}-\mathrm{C}:$
$347,\mathrm{C}=\mathrm{C}:611;\mathrm{C}-\mathrm{H}:414,\mathrm{H}-\mathrm{H}:436]$

JEE Main 2021 (18 Mar Shift 1)

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Question

Five moles of an ideal gas at $293 \mathrm{K}$ is expanded isothermally from an initial pressure of $2.1 \mathrm{MPa}$ to $1.3 \mathrm{MPa}$ against at constant external pressure $4.3 \mathrm{MPa}$. The heat transferred in this process is ___ ${\mathrm{kJmol}}^{-1}$. (Rounded-off to the nearest integer)

[ Use $R=8.314 \mathrm{J} {\mathrm{mol}}^{-1} {\mathrm{K}}^{-1}$]

JEE Main 2021 (25 Feb Shift 2)

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Question

The equilibrium constant $K_c$ at $298 \mathrm{K}$ for the reaction
$\mathrm{A}+\mathrm{B}\rightleftharpoons \mathrm{C}+\mathrm{D}$ is $100 .$ Starting with an equimolar solution with concentrations of $A,B,C$ and $D$ all equal to $1\mathrm{M}$, the equilibrium concentration of $\mathrm{D}$ is _____$\times {10}^{-2}\mathrm{M}$. (Nearest integer)

JEE Main 2021 (26 Aug Shift 2)

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Question

When $400 \mathrm{mL}$ of $0.2 \mathrm{M} {\mathrm{H}}_2{\mathrm{SO}}_4$ solution is mixed with $600 \mathrm{mL}$ of $0.1\mathrm{MNaOH}$ solution, the increase in temperature of the final solution is $—\times {10}^{-2} \mathrm{K}$. (Round off to the nearest integer).

[Use :${\mathrm{H}}^{+}\left(\mathrm{aq}\right)+{\mathrm{OH}}^{-}\left(\mathrm{aq}\right)\to {\mathrm{H}}_2\mathrm{O}:$$\left.{\Delta }_{\gamma }\mathrm{H}=-57.1 \mathrm{kJ}{ \mathrm{mol}}^{-1}\right]$ 

Specific heat of ${\mathrm{H}}_2\mathrm{O}=4.18 \mathrm{J}{ \mathrm{K}}^{-1}{ \mathrm{g}}^{-1}$ , density of ${\mathrm{H}}_2\mathrm{O}=1.0 \mathrm{g}{ \mathrm{cm}}^{-3}$ 

Assume no change in volume of solution on mixing.

JEE Main 2021 (27 Jul Shift 2)

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Question

At $25 °\mathrm{C}$ and $1$ atm pressure, the enthalpies of combustion are as given below:

The enthalpy of formation of ethane is

JEE Main 2022 (24 Jun Shift 2)

Options

• A: $+54.0 \mathrm{kJ}{ \mathrm{mol}}^{-1}$
• B: $-68.0 \mathrm{kJ}{ \mathrm{mol}}^{-1}$
• C: $-86.0 \mathrm{kJ}{ \mathrm{mol}}^{-1}$
• D: $+97.0 \mathrm{kJ}{ \mathrm{mol}}^{-1}$

Question

Match List - I with List - II.

Choose the correct answer from the options given below

JEE Main 2022 (27 Jun Shift 1)

Options

• A: $\left(\mathrm{A}\right)-\left(\mathrm{III}\right),\left(\mathrm{B}\right)-\left(\mathrm{II}\right),\left(\mathrm{C}\right)-\left(\mathrm{IV}\right),\left(\mathrm{D}\right)-\left(\mathrm{I}\right)$
• B: $\left(\mathrm{A}\right)-\left(\mathrm{II}\right),\left(\mathrm{B}\right)-\left(\mathrm{III}\right),\left(\mathrm{C}\right)-\left(\mathrm{IV}\right),\left(\mathrm{D}\right)-\left(\mathrm{I}\right)$
• C: $\left(\mathrm{A}\right)-\left(\mathrm{II}\right),\left(\mathrm{B}\right)-\left(\mathrm{III}\right),\left(\mathrm{C}\right)-\left(\mathrm{I}\right),\left(\mathrm{D}\right)-\left(\mathrm{IV}\right)$
• D: $\left(\mathrm{A}\right)-\left(\mathrm{II}\right),\left(\mathrm{B}\right)-\left(\mathrm{I}\right),\left(\mathrm{C}\right)-\left(\mathrm{III}\right),\left(\mathrm{D}\right)-\left(\mathrm{IV}\right)$

Question

The enthalpy of combustion of propane, graphite and dihydrogen at $298 \mathrm{K}$ are: $-2220.0 \mathrm{kJ}{ \mathrm{mol}}^{-1}$, $-393.5 \mathrm{kJ} {\mathrm{mol}}^{-1}$ and $-285.8 \mathrm{kJ}{ \mathrm{mol}}^{-1}$ respectively. The magnitude enthalpy of formation of propane $\left({\mathrm{C}}_3{\mathrm{H}}_8\right)$ is _____ ${\mathrm{kJmol}}^{-1}$. (Nearest integer)

JEE Main 2022 (25 Jul Shift 1)

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Question

$2.4 \mathrm{g}$ coal is burnt in a bomb calorimeter in excess of oxygen at $298 \mathrm{K}$ and $1 \mathrm{atm}$ pressure.

The temperature of the calorimeter rises from $298 \mathrm{K}$ to $300 \mathrm{K}$. The enthalpy change during the combustion of coal is $-\mathrm{x} \mathrm{kJ}{ \mathrm{mol}}^{-1}$. The value of $\mathrm{x}$ is_____(Given : Heat capacity of bomb calorimeter $20.0 {\mathrm{kJK}}^{-1}$. Assume coal to be pure carbon)

JEE Main 2022 (26 Jul Shift 1)

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Question

A gas ( Molar mass $=280 \mathrm{g}{ \mathrm{mol}}^{-1}$) was burnt in excess ${\mathrm{O}}_2$ in a constant volume calorimeter and during combustion the temperature of calorimeter increased from $298.0 \mathrm{K}$ to $298.45 \mathrm{K}$. If the heat capacity of calorimeter is $2.5 \mathrm{kJ}{ \mathrm{K}}^{-1}$ and enthalpy of combustion of gas is $9 \mathrm{kJ}{ \mathrm{mol}}^{-1}$ then amount of gas burnt is____$\mathrm{g}$.

JEE Main 2022 (27 Jul Shift 2)

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Question

When $5$ moles of $\mathrm{He}$ gas expand isothermally and reversibly at $300 \mathrm{K}$ from $10$ litre to $20$ litre, the magnitude of the maximum work obtained is $\mathrm{J}$. [nearest integer ] (Given : $\mathrm{R}=8.3 \mathrm{J}{ \mathrm{K}}^{-1}{ \mathrm{mol}}^{-1}$ and $\log 2=0.3010$)

JEE Main 2022 (27 Jun Shift 2)

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Question

When $600 \mathrm{mL}$ of $0.2\mathrm{M} {\mathrm{HNO}}_3$ is mixed with $400 \mathrm{mL}$ of $0.1\mathrm{M} \mathrm{NaOH}$ solution in a flask, the rise in temperature of the flask is_____$\times {10}^{-2} °\mathrm{C}$
(Enthalpy of neutralisation $=57 \mathrm{kJ}{ \mathrm{mol}}^{-1}$ and Specific heat of water $=4.2{\mathrm{JK}}^{-1}{ \mathrm{g}}^{-1}$) (Neglect heat capacity of flask)

JEE Main 2022 (29 Jul Shift 1)

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Question

$17.0 \mathrm{g}$ of ${\mathrm{NH}}_3$ completely vapourises at $-33.42 °\mathrm{C}$ and $1$ bar pressure and the enthalpy change in the process is $23.4 \mathrm{kJ}{ \mathrm{mol}}^{-1}$. The enthalpy change for the vapourisation of $85 \mathrm{g}$ of ${\mathrm{NH}}_3$ under the same conditions is $\mathrm{kJ}$.

JEE Main 2022 (29 Jun Shift 1)

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Question

What happens when methane undergoes combustion in systems A and B respectively?

JEE Main 2023 (13 Apr Shift 2)

Options

• A:

  System A	System B
  Temperature rises	Temperature remains same

   

• B:

  System A	System B
  Temperature remains same	Temperature rises

   

• C:

  System A	System B
  Temperature falls	Temperature remains same

• D:

  System A	System B
  Temperature falls	Temperature rises

Question

$28.0$ L of ${\mathrm{CO}}_2$ is produced on complete combustion of $16.8 \mathrm{L}$ gaseous mixture of ethene and methane at $25°\mathrm{C}$ and $1$ atm. Heat evolved during the combustion process is $\mathrm{kJ}$

Given$:{\mathrm{\Delta H}}_{\mathrm{C}}\left({\mathrm{CH}}_4\right)=-900 \mathrm{kJ} {\mathrm{mol}}^{-1}$

${\mathrm{\Delta H}}_{\mathrm{C}}\left({\mathrm{C}}_2{\mathrm{H}}_4\right)=-1400 \mathrm{kJ} {\mathrm{mol}}^{-1}$.

JEE Main 2023 (25 Jan Shift 2)

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Question

The enthalpy of formation of ethane \(\left(\mathrm{C}_2 \mathrm{H}_6\right)\) from ethylene by addition of hydrogen where the bond-energies of \(\mathrm{C}-\mathrm{H}, \mathrm{C}-\mathrm{C}, \mathrm{C}=\mathrm{C}, \mathrm{H}-\mathrm{H}\) are \(414 \mathrm{~kJ}, 347 \mathrm{~kJ}, 615 \mathrm{~kJ}\) and \(435 \mathrm{~kJ}\) respectively is \(\qquad\) \(\mathrm{kJ}\)

JEE Main 2024 (04 Apr Shift 1)

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Question

Combustion of 1 mole of benzene is expressed at \(\mathrm{C}_6 \mathrm{H}_6(\mathrm{l})+\frac{15}{2} \mathrm{O}_2(\mathrm{~g}) \rightarrow 6 \mathrm{CO}_2(\mathrm{~g})+3 \mathrm{H}_2 \mathrm{O}(\mathrm{l}) \text {. }\) The standard enthalpy of combustion of \(2 \mathrm{~mol}\) of benzene is \(-^{\prime} x^{\prime} \mathrm{kJ}\). \(x=\) ______ Given: 1. standard Enthalpy of formation of \(1 \mathrm{~mol}\) of \(\mathrm{C}_6 \mathrm{H}_6(\mathrm{l})\), for the reaction \(6 \mathrm{C}\) (graphite) \(+3 \mathrm{H}_2(\mathrm{~g}) \rightarrow \mathrm{C}_6 \mathrm{H}_6(\mathrm{l})\) is \(48.5 \mathrm{~kJ} \mathrm{~mol}^{-1}\). 2. Standard Enthalpy of formation of \(1 \mathrm{~mol}\) of \(\mathrm{CO}_2(\mathrm{~g})\), for the reaction \(\mathrm{C}\) (graphite) \(+\mathrm{O}_2(\mathrm{~g}) \rightarrow \mathrm{CO}_2(\mathrm{~g})\) is \(-393.5 \mathrm{~kJ} \mathrm{~mol}^{-1}\). 3. Standard and Enthalpy of formation of \(1 \mathrm{~mol}\) of \(\mathrm{H}_2 \mathrm{O}(\mathrm{l})\), for the reaction \(\mathrm{H}_2(\mathrm{~g})+\frac{1}{2} \mathrm{O}_2(\mathrm{~g}) \rightarrow \mathrm{H}_2 \mathrm{O}(\mathrm{l})\) is \(-286 \mathrm{~kJ} \mathrm{~mol}^{-1}\).

JEE Main 2024 (05 Apr Shift 2)

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Question

An ideal gas, \(\overline{\mathrm{C}}_{\mathrm{v}}=\frac{5}{2} \mathrm{R}\), is expanded adiabatically against a constant pressure of 1 atm untill it doubles in volume. If the initial temperature and pressure is \(298 \mathrm{~K}\) and \(5 \mathrm{~atm}\), respectively then the final temperature is _______ \(\mathrm{K}\) (nearest integer). [\(\overline{\mathrm{C}}_{\mathrm{v}}\) is the molar heat capacity at constant volume]

JEE Main 2024 (06 Apr Shift 1)

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Question

If three moles of an ideal gas at $300 \mathrm{K}$ expand isothermally from $30{\mathrm{dm}}^3$ to $45{\mathrm{dm}}^3$ against a constant opposing pressure of $80\mathrm{kPa}$, then the amount of heat transferred is __________J.

JEE Main 2024 (27 Jan Shift 1)

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Question

If $5$ moles of an ideal gas expands from $10\mathrm{L}$ to a volume of $100\mathrm{L}$ at $300\mathrm{K}$ under isothermal and reversible condition then work, $\mathrm{w}$, is $-\mathrm{x} \mathrm{J}$. The value of $\mathrm{x}$ is $-$_______.

(Given $\mathrm{R}=8.314 \mathrm{J} {\mathrm{K}}^{-1} {\mathrm{mol}}^{-1}$)

JEE Main 2024 (31 Jan Shift 2)

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