Advertisements
Advertisements
प्रश्न
The standard molar entropy of \[\ce{H2O (l)}\] is 70 JK–1 mol–1. Will the standard molar entropy of \[\ce{H2O (s)}\] be more, or less than 70 JK–1 mol–1?
उत्तर
The standard molar entropy of \[\ce{H2O (l)}\] is 70 JK–1 mol–1. The solid form of \[\ce{H2O}\] is ice. In ice, molecules of \[\ce{H2O}\] are less random than in liquid water. Thus, molar entropy of \[\ce{H2O (s)}\] < molar entropy of \[\ce{H2O (l)}\]. The standard molar entropy of \[\ce{H2O (s)}\] is less than 70 JK–1 mol–1.
APPEARS IN
संबंधित प्रश्न
Define molar heat capacity.
Write the unit of molar heat capacity.
During complete combustion of one mole of butane, 2658 kJ of heat is released. The thermochemical reaction for above change is ______.
\[\ce{∆_f U^Θ}\] of formation of \[\ce{CH4 (g)}\] at certain temperature is – 393 kJ mol–1. The value of \[\ce{∆_f H^Θ}\] is ______.
On the basis of thermochemical equations (a), (b) and (c), find out which of the algebric relationships given in options (i) to (iv) is correct.
(a) \[\ce{C (graphite) + O2 (g) -> CO2 (g) ; ∆_rH = xkJ mol^{-1}}\]
(b) \[\ce{C (graphite) + 1/2 O2 (g) -> CO (g) ; ∆_rH = ykJ mol^{-1}}\]
(c) \[\ce{CO (g) + 1/2 O2 (g) -> CO2 (g) ; ∆_r H = zkJ mol^{-1}}\]
The molar enthalpy of vapourisation of acetone is less than that of water. Why?
If the combustion of 1g of graphite produces 20.7 kJ of heat, what will be molar enthalpy change? Give the significance of sign also.
Derive the relationship between ∆H and ∆U for an ideal gas. Explain each term involved in the equation.
The molar heat of formation of NH4NO3 (s) is −367.54 kJ and those of N2O (g), H2O (l) are 81.46 and −285.8 kJ respectively at 25°C and atmosphere pressure. The difference of ΔH and ΔE of the reaction \[\ce{NH4NO3(s) -> N2O (g) + 2H2O (l)}\] is ______ kJ.
A cylinder of gas supplied by Bharat Petroleum is assumed to contain 14 kg of butane. If a normal family requires 20,000 kJ of energy per day for cooking, butane gas in the cylinder last for ______ Days. (Δ Hc of C4 H10 = - 2658 JK per mole)
