Advertisements
Advertisements
प्रश्न
Value of universal gas constant (R) is same for all gases. What is its physical significance?
Advertisements
उत्तर
Unit of R depends on the units of p, V and T are measured, We know, `R = (pV)/(nT)`
Now, let's say, the pressure is measured in Pascal, per mole volume is measured in m3 and temperature is measured in Kelvin, then. Units of ‘R’ are Pa m3K–1 mol–1. Also, R is work done per mole per kelvin. It’s unit is J K–1 mol–1 (Joule is the unit of work done).
APPEARS IN
संबंधित प्रश्न
Which of the following is the correct expression for the equation of state of van der Waals gas?
The value of the universal gas constant depends upon
Compressibility factor for CO2 at 400 K and 71.0 bar is 0.8697. The molar volume of CO2 under these conditions is
Maximum deviation from ideal gas is expected from
Which of the following diagrams correctly describes the behaviour of a fixed mass of an ideal gas? (T is measured in K)
25 g of each of the following gases are taken at 27°C and 600 mm Hg pressure. Which of these will have the least volume?
Can a Van der Waals gas with a = 0 be liquefied? explain.
Suppose there is a tiny sticky area on the wall of a container of gas. Molecules hitting this area stick there permanently. Is the pressure greater or less than on the ordinary area of walls?
Explain whether a gas approaches ideal behavior or deviates from ideal behaviour if the temperature is raised while keeping the volume constant.
Under which of the following two conditions applied together, a gas deviates most from the ideal behaviour?
(i) Low pressure
(ii) High pressure
(iii) Low temperature
(iv) High temperature
Compressibility factor, Z, of a gas is given as Z = `(pV)/(nRT)`. What is the value of Z for an ideal gas?
Compressibility factor, Z, of a gas is given as Z = `(pV)/(nRT)`. For real gas what will be the effect on value of Z above Boyle’s temperature?
Match the following graphs of ideal gas with their co-ordinates:
| Graphical representation | x and y co-ordinates |
(i)  |
(a) pV vs. V |
(ii)  |
(b) p vs. V |
(iii)  |
(c) p vs. `1/V` |
Assertion (A): At constant temperature, pV vs V plot for real gases is not a straight line.
Reason (R): At high pressure all gases have \[\ce{Z}\] > 1 but at intermediate pressure most gases have \[\ce{Z}\] < 1.
Isotherms of carbon dioxide gas are shown in figure. Mark a path for changing gas into liquid such that only one phase (i.e., either a gas or a liquid) exists at any time during the change. Explain how the temperature, volume and pressure should be changed to carry out the change.
In van der Waal's equation for the real gas, the expression for the net force of attraction amongst the gas molecules is given by:
