Chemistry Question Bank

The densities of graphite and diamond at 298 K are 2.25 and 3.31 g cm–3, respectively. If the standard free energy difference is equal to 1895 J mol–1, the pressure at which graphite will be transformed into diamond a…

For the reaction, 2H O g 2H g O g → ∆H = 571.6 KJ fH of water is :

When 0.5 g of sulphur is burnt to SO₂ 4.6 kJ of heat is liberated. What is the enthalpy of formation of sulphurdioxide?

The heat of formation of Fe O s is –824.2 kJ mol–1. ∆H for the reaction. 2Fe O s 4Fe s 3O g → is:

The molar heat capacity of water at constant pressure, C, is 75J K-1. When 1.0 kJ of heat is supplied to 100 g of water which is free to expand, the increase in temperature of water is. (2003)

If the bond energies of H–H, Br–Br, and H–Br are 433, 192 and 364 kJ mol–1 respectively, the H for the reaction 2(g) 2(g) (g) H Br 2HBr → is (2004)

The absolute enthalpy of neutralisation of the reaction: (g) (g) 2(aq) (l) MgO 2HCl MgCl H O → Will be (2005)

A reaction occurs spontaneously if (2005)

The enthalpy and entropy change for the reaction: 2(l) 2(g) (g) Br Cl 2BrCl → are 30 kJ mol–1 and 105JK–1 mol–1 respectively. The temperature at which the reaction will be in equilibrium is (2006)

Consider the following reaction –1 (aq) (aq) (l) –1 2(g) 2(g) (l) 2(g) 2(g) (g) (l) –1 2(g) 2(g) 2(g) (l) –1 (i)H OH H O , H X kJ mol (ii)H 1/ 2O H O , H X kJ mol (iii)CO H CO H O , H X kJ mol (iv)C H 5 / 2O 2CO H O ,…

For the gas phase reaction, 5(g) 3(g) 2(g) PCl PCl Cl Which of the following conditions are correct? (2008)

Bond dissociation enthalpy of H₂ Cl₂, and HCl are 434, 242 and 431 kJ mol respectively. Enthalpy of formation of HCl is (2008)

Gaseous system is placed with pressure P₁, volume V₁ and  temperature  T1,  it  has  undergone  thermodynamic changes where temperature is remaining constant, it is

Based on the first law of thermodynamics, which one of the following is correct?

U q w , is mathematical expression for

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?

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:

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?

The maximum work obtained by an isothermal reversible expansion of 1 mole of an ideal gas at 27°C from 2.24 to 22.4 L is (R = 2 cal)

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

The work done during the expansion of a gas from a volume of 4dm3 to 6 dm3 against a constant external pressure of 3 atm is

The following two reactions are known Fe₂O₃(s) + 3CO(g) → 2Fe(s) + 3CO₂(g); ∆H = –26.8 kJ FeO(s) + CO(g) → Fe(s) + CO₂(g); ∆H = – 16.5 kJ The value of ∆H for the following reaction Fe₂O₃(s) + CO(g) → 2FeO(s) + CO₂(g) …