Chemistry Question Bank

Two moles of Helium gas undergo a reversible cyclic process as shown in figure. Assuming gas to be ideal. What is the work done for the process C to D?

E is always positive, when

An ideal gas is taken around the cycle ABCA as shown in P-V diagram The net work done by the gas during the cycle is equal to:

An ideal gas receives 10 J of heat in a reversible isothermal expansion. Then the work done by the gas:

A given mass of gas expands from state A to state B by three paths 1, 2, and 3 as shown in the figure: If w ,w  and w  respectively, be the work done by the gas along three paths, then (a) w w w (b) w w w

One mole of an ideal gas is initially at 0°C and 1 atm pressure. If it absorbs 1000 cal heat during a reversible isothermal expansion, what will be its final volume?

Calculate the work done when 1 mol of an ideal gas is compressed reversibly from 1 bar to 4 bar at a constant temperature of 300 K

16g of oxygen gas expands isothermally and reversibly at 300 K from 10 dm3 to 100 dm3. The work done is (in J)

For a given reaction, ∆H = 35.5 kJ mol–1 and ∆S = 83.6 J K–1 mol–1. The reaction is spontaneous at (Assume that ∆H and ∆S do not vary with temperature.) (NEET 2017)

In which case change in entropy is negative? (NEET 2019)

Which one of the following has  S  greater than zero? (a) CaO s CO g CaCO s (b) NaCl aq NaCl s (c) NaNO s Na aq NO aq (d) N g 3H g 2NH g

Which of the following expressions regarding entropy is not correct? (a) system q S T (b) system total surrounding S S S (c) final initial S S S (d) total system surrounding S S S

G T S  when H

G H T S when H S Hence, Correct option is c

Unit of entropy is

In which case change in entropy is negative?

For the reaction, X2O₄(l) → 2XO₂(g) ∆U = 2.1 kcal, ∆S = 20 cal K–1 at 300 K Hence, ∆G is (2014)

When 5 litres of a gas mixture of methane and propane is perfectly combusted at 0°C and 1 atmosphere, 16 litres of oxygen at the same temperature and pressure is consumed. The amount of heat released from this combust…

The heat of combustion of carbon to CO₂ is –393.5 kJ/mol. The heat released upon formation of 35.2 g of CO₂ from carbon and oxygen gas is (2015)

One mole of an ideal gas expands reversibly and adiabatically from a temperature of 27°C. If the work done during the process is 3 kJ, then final temperature of the gas is:(CV = 20 J/K)

According to the first law of thermodynamics, U q w . In special cases the statement can be expressed in different ways. Which of the following is not a correct expression?

The enthalpy of vaporisation of a compound AB at its boiling point (127°C) is 6.4 kJ mol-1. Its entropy of vaporization is

For a sample of perfect gas when its pressure is changed isothermally from pi to pf, the entropy change is given by. (NEET-II 2016)

For the reaction, 2Cl(g) → Cl₂(g), the correct option is (NEET 2020)

The statement “The change of enthalpy of a chemical reaction is same whether the reaction takes place in one or several steps” is