Heat & Thermodynamics MCQs with Answers

Water has a high boiling point because?

• A.It is a universal solvent
• B.It has a low molecular mass
• C.It contains dissolved gases
• D.Molecules are associated by hydrogen bonding

When 1 mole of ice melts at 0°C and constant pressure of 1 atmosphere, 6025 J of heat is absorbed by the system. The molar volume of ice and water are 0.020 dm³ and 0.018 dm³, respectively. Calculate ∆E. (1 dm³·atm = 101.33 J)

• A.6025.20 J
• B.6022.97 J
• C.6027.43 J
• D.6024.80 J

Past Paper MCQ

In the absence of any transmission medium, heat can be transferred from one place to another place, by _?

• A.Conduction
• B.Convection
• C.Radiation
• D.Both conduction and convection

If a reaction has negative enthalpy (ΔH < 0) and positive entropy (ΔS > 0), then the reaction is:

• A.Non-spontaneous at all temperatures
• B.Spontaneous only at high temperatures
• C.Spontaneous at all temperatures
• D.Spontaneous only at low temperatures

The entropy of steam is than ice.

• A.Greater
• B.Less
• C.Equal
• D.None of these

Solar radiation emitted by sun resembles that emitted by a black body at a temperature of 6000K. Maximum intensity is emitted at a wavelength of about 4800A°. If the sun was cooled down from 6000 K to 3000 K then the peak intensity would occur at a wavelength of ?

• A.2400 A°
• B.4800 A°
• C.9600 A°
• D.19200 A°

When the temperature of a copper penny is increased by 100 °C, its diameter increases by 0.17%. The area of one of its faces increases by:

• A.0.17%
• B.0.34%
• C.0.51%
• D.0.085%

Thermodynamically spontaneous reactions are _.

• A.Always fast
• B.Always slow
• C.Neither slow nor fast
• D.Always instantaneous

The coefficient of transmission and coefficient of reflection for a given body at a given temperature are 0.33 and 0.64 respectively. Then the coefficient of emission of the same body at the same temperature will be ?

• A.0.03
• B.0.31
• C.0.97
• D.0.67

The Carnot cycle can be shown by _?

• A.P-V graph
• B.V-T graph
• C.P-T graph
• D.None of these