First law of thermodynamics for an isolated system is also called as law of conservation of energy.

Important Questions on Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

A system does $200 \mathrm{J}$ of work and at the same time absorbs $150 \mathrm{J}$ of heat. The magnitude of the change in internal energy is  ______$\mathrm{J}$. (Nearest integer)

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

Five moles of an ideal gas at $1$ bar and $298 \mathrm{K}$ is expanded into vacuum to double the volume. The work done is :

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

$365$ calorie heat is required to evaporate one gram water at $100{}^{\circ }\mathrm{C}$. If the work done by the system is $651.3$ calorie, then the increase in internal energy per mole of water will be

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

When a gas is allowed to expand in a well-insulated container, against a constant external pressure of $5$ atm, from an initial value of $10 \mathrm{L}$ to a final volume of $15 \mathrm{L},$ find the change in the internal energy $\left(\mathrm{\Delta U}\right)$ of the gas.

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

The above $P-V$ diagram represents the thermodynamic cycle of an engine, operating with an ideal mono-atomic gas. The amount of heat, extracted from the source in a single cycle, is:

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

A system undergoes a process in which $\mathrm{\Delta U}=+300 \mathrm{J}$ while absorbing $400 \mathrm{J}$ of heat energy and undergoing an expansion against $0.5$ bar. What is the change in volume (in $\mathrm{L}) ?$

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

The correct option for free expansion of an ideal gas under adiabatic condition is

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

If work done by the system is $300$ Joule when $100$ Cal, heat is supplied to it. The change in internal energy during the process is :-

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

The molar enthalpy change for ${\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)\rightleftharpoons {\mathrm{H}}_2\mathrm{O}\left(\mathrm{g}\right)$ at $373 \mathrm{K}$ and $1 \mathrm{atm}$ is $40\mathrm{ }\mathrm{kJ}/\mathrm{mol}$ . Assuming ideal behaviour, the internal energy change for vaporization of $1 \mathrm{mol}$ of water at $373 \mathrm{K}$ and $1 \mathrm{atm}$ in $\mathrm{kJ}\mathrm{ }{\mathrm{mol}}^{-1}$ is:

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

During compression of a spring the work done is $10\mathrm{ }\mathrm{k}\mathrm{J}$ and $2\mathrm{ }\mathrm{k}\mathrm{J}$ escaped to the surroundings as heat. The change in internal energy, $\mathrm{\Delta }\mathrm{U}\left(\mathrm{i}\mathrm{n}\mathrm{k}\mathrm{J}\right)$ is:

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

A system absorbs $6 \mathrm{kJ}$ of heat and does $1.5 \mathrm{kJ}$ of work on its surroundings. The change in internal energy is _____.

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

$\mathrm{\text{Δ}}\text{U}$ is equal to:

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

5 moles of helium expand isothermally and reversibly from a pressure $40\times {10}^{-5 } {\mathrm{Nm}}^{-2 } \mathrm{to} 4\times {10}^{-5 } {\mathrm{Nm}}^{-2 }$ at 300 K. Calculate the work done, change in internal energy and heat absorbed during the expansion. $(\mathrm{R}=8.314 {\mathrm{JK}}^{-1}{\mathrm{mol}}^{-1})$

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

When the temperature of $2$ moles of an ideal gas is increased by $20°\mathrm{C}$ at constant pressure, find the work involved in the process.

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

A system gives out $30 \mathrm{J}$ of heat and does $75 \mathrm{J}$ of work. What is the internal energy change?

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

Consider two states, $\mathrm{A}$ and $\mathrm{B}$, of a thermodynamic system. Let Path $1$ represent a reversible process for going from $\mathrm{A}$ to $\mathrm{B}$, while Path $2$ represents an irreversible process for the same. Let the work done, heat change, and entropy change for the two processes be denoted by ${\mathrm{dw}}_{\mathrm{rev} },{\mathrm{dq}}_{\mathrm{rev} },{\mathrm{dS}}_{\mathrm{rev} }$ and ${\mathrm{dw}}_{\mathrm{irrev} },{\mathrm{dq}}_{\mathrm{irrev} },{\mathrm{dS}}_{\mathrm{irrev} }$, respectively. It is observed that the relation ${\mathrm{dw}}_{\mathrm{rev}}<{\mathrm{dw}}_{\mathrm{irrev} }$ is obeyed. The correct statement is

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

Mathematical statement of the first law of thermodynamics is

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

Following figure shows two processes $\mathrm{A}$ and $\mathrm{B}\mathrm{ }$ for a gas. If $∆{\mathrm{Q}}_{\mathrm{A}}$ and $∆{\mathrm{Q}}_{\mathrm{B}}$ are the amount of heat absorbed by the system in two cases, and $∆{\mathrm{U}}_{\mathrm{A}}$ and $∆{\mathrm{U}}_{\mathrm{B}}$ are changes in internal energies, respectively, then:

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

A gas undergoes change from state $\mathrm{A}$ to state $\mathrm{B}$. In this process, the heat absorbed and work done by the gas is $5 \mathrm{J} \text{and} 8 \mathrm{J}$, respectively. Now gas is brought back to $\mathrm{A}$ by another process during which $3 \mathrm{J}$ of heat is evolved. In this reverse process of $\mathrm{B} \mathrm{to} \mathrm{A}$.

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

A piston filled with 0.04 mol of an ideal gas expands reversibly from 50.0 mL to 375 mL at a constant temperature of $37.0^{\circ }\text{C}$. As it does so, it absorbs 208 J of heat. The values of q and w for the process will be 
(R = 8.314 J/mol K) (ln7.5 = 2.01)