Medical Sample papers

# Thermodynamics Question Bank Thermochemistry and Thermodynamics Multiple Choice Questions based NEET Medical Entrance Exam.

## NEET Thermodynamics Practice Question / Answers

 Question 1
Mass and energy are conserved is demonstrated by
 A Modified form of Ist law of thermodynamics B Law of conservation of mass C Law of conservation of energy D First law of thermodynamics
 Question 2
Two rectangular blocks A and B of different metals have same length and same area of crosssection. They are kept in such a way that their cross-sectional area touch each other. The temperature at one end of A is 100°C and that of B at the other end is 0°C. If the ratio of their thermal conductivity is 1 : 3, then under steady state, the temperature of the junction in contact will be
 A 75°C B 50°C C 25°C D 100°C
 Question 3
In variable state, the rate of flow of heat is controlled by
 A All the these factors B Density of material C Specific heat D Thermal conductivity
 Question 4
The heat is flowing through two cylindrical rods of same material. The diameters of the rods are in the ratio 1 : 2 and their lengths are in the ratio 2 : 1. If the temperature difference between their ends is the same, the ratio of rate of flow of heat through them will be
 A 1 : 1 B 1 : 4 C 2 : 1 D 1 : 8
 Question 5
The length of the two rods made up of the same metal and having the same area of cross-section are 0.6 m and 0.8 m respectively. The temperature between the ends of first rod is 90oC and 60oC and that for the other rod is 150 and 110oC. For which rod the rate of conduction will be greater
 A First B Same for both C None of the above D Second
 Question 6
For cooking the food, which of the following type of utensil is most suitable
 A Low specific heat and high conductivity B Low specific heat and low conductivity C High specific heat and high conductivity D High specific heat and low conductivity
 Question 7
The thickness of a metallic plate is 0.4 cm. The temperature between its two surfaces is 20oC. The quantity of heat flowing per second is 50 calories from 5cm2 area. In CGS system, the coefficient of thermal conductivity will be
 A 0.5 B 0.6 C 0.2 D 0.4
 Question 8
A gas expands with temperature according to the relation V = KT2/3 What is the work done when the temperature changes by 30oC
 A 40 R B 10 R C 30 R D 20 R
 Question 9
A piece of glass is heated to a high temperature and then allowed to cool. If it cracks, a probable reason for this is the following property of glass
 A High specific heat B High thermal conductivity C High melting point D Low thermal conductivity
 Question 10
A slab consists of two parallel layers of copper and brass of the same thickness and having thermal conductivities in the ratio 1 : 4. If the free face of brass is at 100oC and that of copper at 0oC, the temperature of interface is
 A 20°C B 60°C C 80°C D 40°C
 Question 11
The temperature gradient in a rod of 0.5 m long is 80°C/m. If the temperature of hotter end of the rod is 30°C/m, then the temperature of the cooler end is
 A 10°C B 40°C C 0°C D -10°C
 Question 12
In a thermodynamic process pressure of a fixed mass of a gas is changed in such a manner that the gas releases 30 joules of heat and 10 joules of work was done on the gas. If the initial internal energy of the gas was 30 joules, then the final internal energy will be
 A 2 J B 58 J C 10 J D – 18 J
 Question 13
Which of the following cylindrical rods will conduct most heat, when their ends are maintained at the same steady temperature
 A Length 1 m; radius 2 cm B Length 1 m; radius 1 cm C Length 2 m; radius 1 cm D Length 2 m; radius 2 cm
 Question 14
Two vessels of different materials are similar in size in every respect. The same quantity of ice filled in them gets melted in 20 minutes and 30 minutes. The ratio of their thermal conductivities will be
 A 4 B 2/3 C 1 D 1.5
 Question 15
Under steady state, the temperature of a body
 A Does not change with time and is same at all the points of the body B Does not change with time but is different at different points of the body C Increases with time D Decreases with time
 Question 16
Heat exchanged in a chemical reaction at constant temperature and constant pressure is called as
 A Enthalpy B Free energy C Entropy D Internal energy
 Question 17
In the case of diatomic gas, the heat given at constant pressure is that part of energy which is used for the expansion of gas, is
 A 2/7 B 3/7 C 5/7 D 2/5
 Question 18
The heat content of a system is called
 A Free energy B Entropy C Internal energy D Enthalpy
 Question 19
When a gas undergoes adiabatic expansion, it gets cooled due to loss of kinetic energy
 A Fall in temperature B Decrease in velocity C Energy used in doing work D Loos of kinetic energy
 Question 20
The value of heat generated when 36.5 gm HCl and 40 gm of NaOH reacts during neutralization
 A 13.7 kcal B 76.5 kcal C 108 kcal D More than 13.7 kcal
 Question 21
What is the entropy change (in JK–1 mol–1) when one mole of ice is converted into water at 0oC (The enthalpy change for the conversion of ice to liquid water is 6.0 kJ mol–1 at 0o C)
 A 21.98 B 20.13 C 2.013 D 2.198
 Question 22
In Searle's method for finding conductivity of metals, the temperature gradient along the bar
 A Increases as we go from hot end to cold end B Is greater nearer to the cold end C Is the same at all points along the bar D Is greater nearer the hot end
 Question 23
The coefficient of thermal conductivity depends upon
 A Thickness of the plate B Temperature difference of two surfaces C Material of the plate D Area of the plate
 Question 24
Two mole of an ideal gas is expanded isothermally and reversibly from 1 litre ot 10 litre at 300 K. The enthalpy change (in kJ) for the process is
 A 11.4 kJ B –11.4 kJ C 0 kJ D 4.8 kJ
 Question 25
Snow is more heat insulating than ice, because
 A Air is filled in porous of snow B Density of ice is more C Air is filled in porous of ice D Ice is more bad conductor than snow
 Question 26
The ratio of thermal conductivity of two rods of different material is 5 : 4. The two rods of same area of cross-section and same thermal resistance will have the lengths in the ratio
 A 4 : 5 B 9 : 1 C 1 : 9 D 5 : 4
 Question 27
In which case the thermal conductivity increases from left to right
 A Al, Ag, Cu B Ag, Cu, Al C Cu, Ag, Al D Al, Cu, Ag
 Question 28
The internal energy of an ideal gas increases during an isothermal process when the gas is
 A Expanded by adding more molecules to it B Expanded by adding more heat to it C Expanded against zero pressure D Compressed by doing work on it
 Question 29
When two ends of a rod wrapped with cotton are maintained at different temperatures and after some time every point of the rod attains a constant temperature, then
 A Each point of the rod is giving heat to its neighbour at the same rate at which it is receiving heat B Conduction of heat at different points of the rod stops because the temperature is not increasing C Heat is being radiated from each point of the rod D Rod is bad conductor of heat
 Question 30
In an adiabatic process 90J of work is done on the gas. The change in internal energy of the gas is
 A +90 J B 0 J C – 90 J D Depends on initial temperature
There are 30 questions to complete. 