Questions
A temperature difference of 5oC on Celsius scale corresponds to the following temperature in the Fahrenheit scale.
- 41
- 32.05
- 33
- 77
- 13
In a temperature scale called Z, the boiling point of water is at 65oZ and the freezing point is at - 14oZ. Then the temperature T = - 98oZ corresponds on the Fahrenheit scale to
- - 159oF
- - 363oF
- - 223oF
- - 427oF
- - 72oF
A tap supplies water at 10oC and another tap at 100oC. How much hot water must be taken so that we get 20 kg of water at 35oC?
- 5.56 kg
- 8.18 kg
- 12.5 kg
- 45 kg
- 4.54 kg
The first excited state of hydrogen atom is 10.2 e V above the ground state. What temperature is needed to excite hydrogen atoms to first excited level?
- 7.88 x 104 K
- 3.94 x 104 K
- 5.91 x 104 K
- 23.65 x 104 K
-
17.73 x 104 K
At what temperature will the root mean square velocity of oxygen molecules be sufficient, so as to escape from the earth?
- 1.6 x 105 K
- 28.63 K
- 14.31 K
- 21.47 K
- 42.95 K
A gas is filled in a container at pressure P0. If the mass of each molecule is halved and speeds are double, then the resulting pressure will be
- 2 Po
- 4 Po
- Po
- Po/2
- 8 Po
The density of carbon dioxide gas at 0oC and at a pressure of 1.0 x 105 Newton/metre2 is 1.98kg/m3. Find the root mean square velocity of its molecules at 0oC.
- 389 m/s
- 1.5 x 105 m/s
- 5.05 x 104 m/s
- 224 m/s
- 1.68 x 104 m/s
A flask of 10-3 m3 volume contains 3 x 1022 molecules of oxygen at a certain temperature. The mass of one molecule of oxygen is 5.3 x 10-26 kg and rms velocity of its molecules at the same temperature is 400m/s. Calculate the pressure of the gas.
- 8.48 x 104 N/m2
- 25.44 x 104 N/m2
- 636 N/m2
- 212 N/m2
- 2.12 x 10-4 N/m2
Calculate the kinetic energy of a gram molecule of argon at 127oC.
- 4986 J
- 9972 J
- 1662 J
- 6648 J
- 2216 J
5 g of ice at 0oC is dropped in a beaker containing 20 g of water at 40oC. What will be the final temperature?
- 16oC
- 26.66oC
- - 16oC
- - 26.66oC
- 35.29oC
At what temperature does the average translational kinetic energy of a molecule in a gas equal to the kinetic energy of an electron accelerated from rest through a potential difference of 5 volt?
- 38.65 x 10<sup style="font-family:">3 K
- 8.69 x 10<sup style="font-family:">4 K
- 1.93 x 10<sup style="font-family:">4 K
- 2.89 x 10<sup style="font-family:">4 K
- 11.59 x 10<sup style="font-family:">4 K
If the pressure of a gas containing vessel increases by 0.5% when heated by 2oC, then the initial temperature must be
- 127oC
- 400oC
- 673oC
- 1073oC
-
527oC
The pressure of a gas is P N/m2. The mean kinetic energy of one gram – mole at NTP ( in joule) will be
- 3.36 x 10-2 P
- 2.24 x 10-2 P
- 6.72 x 10-2 P
- 4.48 x 10-2 P
- 2.24 x 10-2 P
At what temperature will the root mean square velocity of hydrogen be double of its value at S.T.P. , pressure remaining constant?
- 819oC
- 1092oC
- 1365oC
- 819oC
- 273oC
The specific heat of argon at constant volume is 0.075 kcal/kg K. Calculate the atomic weight.
[Given: R = 2cal/mol K]
- 40 gm/mole
- 53.33 gm/mole
- 17.77 gm/mole
- 0.225 gm/mole
-
0.1 gm/mole
A gram molecule of a gas is allowed to expand adiabatically at 327oC till the volume is four times the initial volume. Calculate the amount of heat absorbed.
J = 4.2 x 107 ergs/cal, R = 8.31 x 107 ergs/gm mole oC and γ = 1.5
- 1187.14 cal
- 20941.2 x 1014 cal
- 593.57 cal
- 2374.28 cal
- 3561.42 cal
At the top of a mountain, a thermometer reads 7oC and barometer reads 70 cm of Hg. At the bottom of the mountain, they read 27oC and 76 cm of Hg. Compare the air at the top with that at the bottom.
- 0.9868
- 3.55
- 1.01
- 0.28
- 0.072