Molecular Physics | Thermodynamics Answers

An ice sculpture is made of 55 kg of ice and is stored at –22˚C. Heat is turned on instead of the cold and evaporates all the ice into steam at a temperature of 115˚C. How much heat was added to the sculpture to create the sauna? (grade 11 physics)

Ten moles of a monaatomic ideal gas initially has a volume of 0.800m3. The gas undergoes four processes: 1) without changing its temperature, the gas expands to a volume of 1.200m3, at which point its pressure is 20.00KPa, 2) The gas expands to a volume of 1.480m3 without heat entering or leaving the gas. 3) without changing its temperature, the gas is compressed until its pressure is 21.15KPa. 4) The gas is compressed to a pressure of 30.00KPa without heat entering or leaving the gas.

I) calculate the work done by the gas in processes 1) and 3).

II) Determine the process that the gas undergoes

III) Using the definition of the entropy, calculate the total change in entropy during the four processes. Comment on your answer.

If the Fermi energy of silver is 5.5 eV, the wave number of the fastest electron at 0 K has the magnitude in (meter)^-1 is?

Assuming the ideal C/a ratio for the HCP Ti (with a=2.95 Angstrum ), the radius of the largest sphere that will fit interstitially in Ti is?

If the activation energy for oxidation is 100 KJ mole^-1 , the ratio of oxidation rates at

800 degree Celcius and 500 degree Celcius is ?

The maximum possible decrease in energy during the grain-growth of Copper, where the grain boundary energy is 0.5Jm^-2 and the initial grain diameter is 0.3mm is?

For the same diffusion time, the depth of penetration at 500 degree celcius and 850 degree celcius is in the ratio 1:6. The activation process for the above diffusion process is?

A certain perfect gas is heated at constant pressure from 15 degrees celcius to 95 degrees celcius, the energy required is 1136 KJ / kg.

When this same gas is heated at constant volume to the same temperatures, the energy required is 808

KJ / kg. Calculate:

(i) Mass heat at constant pressure, cp

(ii) Mass heat at constant volume, CV

(iii) The value of γ

(iv) The particular gas constant, Rp

(v) Molar mass, Mr

A certain perfect gas is heated at constant pressure from 15 degrees celcius to 95 degrees celcius, the energy required is 1136 KJ / kg.

When this same gas is heated at constant volume to the same temperatures, the energy required is 808

KJ / kg.

Calculate:

(i) Mass heat at constant pressure, cp

(ii) Mass heat at constant volume, CV

(iii) The value of γ

(iv) The particular gas constant, Rp

(v) Molar mass, Mr

Oxygen , at a pressure of 200 bars, will be contained in a steel container at a temperature of 20 degrees celcius.

The volume of the container is 0.04 m3. Assuming that Oxygen is an ideal gas, calculate the mass of Oxygen which can

be contained in the container.

The container is protected against excessive pressure by a fusible plug which will melt if the temperature

goes too high.

Calculate at what temperature the fuse plug will melt if the pressure is limited to 240 bar.

(The molar mass of oxygen = 32 Kg / Kmol and Ru = 8314 J / Kmol K)