First Law of Thermodynamics

If $\mathrm{\Delta H}$ is the change in enthalpy and $\mathrm{\Delta E},$ the change in internal energy accompanying a gaseous reaction, then

A gas is enclosed in a cylinder with a piston. Weights are added to the piston, giving a total mass of $2.20 \mathrm{kg}$. As a result, the gas is compressed and the weights are lowered $0.25 \mathrm{m}$. At the same time, $1.50 \mathrm{J}$ of heat is evolved from the system. Calculate the change in internal energy of the system and report the answer in the nearest integer value

Find the change in the internal energy $\left(\mathrm{\Delta U}\right)$ of a closed system, when $\text{'}\mathrm{w}\text{'}$ denotes the  amount of work done by the system and $\text{'}\mathrm{q}\text{'}$ amount of heat is supplied to the system.

$∆\mathrm{U}=\mathrm{q}+\mathrm{W}$ is mathematical expression for

State first law of thermodynamics. Justify its mathematical equation.
 

Consider an ideal gas which undergoes a cyclic process as below:

${\text{ΔU}}_{\mathrm{BC}}=-5{\mathrm{kJmol}}^{-1}$

${\text{q}}_{\mathrm{AB}}=2{\mathrm{kJmol}}^{-1}$

${\text{W}}_{\mathrm{AB}}=-5{\mathrm{kJmol}}^{-1}$

${\text{W}}_{\mathrm{CA}}=3{\mathrm{kJmol}}^{-1}$

Then the Heat absorbed by the system during process CA is ____ ${\mathrm{kJmol}}^{-1}$

Air separated from the atmosphere by a column of mercury of length $h=15 \mathrm{cm}$ is present in a narrow cylindrical soldered at one end. When the tube is placed horizontally the air occupies a volume $V_1=250 {\mathrm{mm}}^3$. When it is set vertically with its open end upwards the volume of the air is $V_2=200 {\mathrm{mm}}^3$. The atmospheric pressure during the experiment is $x \mathrm{cm} \text{of} \mathrm{Hg}$. Find $x$.

A cylinder of ideal gas is closed by a $4\mathrm{k}\mathrm{g}$ movable piston of area $30{\mathrm{c}\mathrm{m}}^2$. When the gas is heated from ${50}^{\mathrm{o}}\mathrm{C}$ to ${100}^{\mathrm{o}}\mathrm{C}$, the piston raises $20\mathrm{c}\mathrm{m}$. The piston is then held in place and the gas is cooled back to ${50}^{\mathrm{o}}\mathrm{C}$. If $Q_1$ is the heat added to the gas in the heating process and ${\mathrm{Q}}_2$ is the heat lost during cooling, then $\left(Q_1–Q_2\right)$ can be approximated as $10\lambda$, where $\lambda$ is an integer between (0 to 9). Find $\lambda$.
Given : P_atm = 1 × 10⁵ N/m²
g = 9.8 m/sec²

A system absorbs $50\mathrm{ }\mathrm{k}\mathrm{J}$ of heat and does $20 \mathrm{kJ}$ of work. What is the net change in the internal energy of the system?

What will be the change in internal energy when $12\mathrm{ }\mathrm{k}\mathrm{J}$ of work is done on the system and $2\mathrm{ }\mathrm{k}\mathrm{J}$ of heat is given by the system?

In an adiabatic expansion of an ideal gas

Temperature of 4 moles of an ideal gas is raised from 300K to 350K. What is the value of $\mathrm{\Delta H}-\mathrm{\Delta E}$ for this process? $\left(\mathrm{R}=8.3\mathrm{J}\mathrm{ }{\mathrm{mol}}^{-1}{\mathrm{K}}^{-1}\right)$

Ideal gas is contained in a thermally insulated and rigid container and it is heated through a resistance $100\mathrm{\Omega }$ by passing a current of 1A for five minutes, then change in internal energy of the gas is

The molar heat capacity of water at constant pressure is $75\mathrm{ }\mathrm{J}{\mathrm{K}}^{-1}\mathrm{ }\mathrm{m}\mathrm{o}{\mathrm{l}}^{-1}$ . When 1KJ of heat is supplied to 100 g of water, which is free to expand the increase in temperature of water is

A heat engine absorbs heat $Q_1$ at temperature $T_1$ and heat $Q_2$ at temperature $T_2$ . Work done by the engine is $J \left(Q_1+Q_2\right).$ This data

For a cyclic process, which of the following is not true?

A heat engine absorbs heat $Q_1$ at temperature $T_1$ and heat $Q_2$ at temperature $T_2$ . Work done by the engine is $J \left(Q_1+Q_2\right).$ This data

The bond energy of ${\mathrm{H}}_2$ is $104.3\mathrm{ }\mathrm{K}.\mathrm{c}\mathrm{a}\mathrm{l}\mathrm{ }\mathrm{m}\mathrm{o}{\mathrm{l}}^{-1}$ . It means that

Work Done in Thermodynamical Process, $1^{\mathrm{s}\mathrm{t}}$ Law, Internal Energy & Heat Capacity. The internal energy when a system goes from state A to B is 40 kJ/mol. If the system goes from A to B by a reversible path and returns to state A by an irreversible path. What would be the net change in internal energy?