Question

Molecule of one mole gas at NTP, each having a radius of ${10^{ - 8}}$ cm occupies volume?
A.22.0 litre
B.22.4 litre
C.10.09 ml
D.10.08 litre

Answer 1

Hint: In simple language: STP stands for Standard Temperature and Pressure. NTP stands for Normal Temperature and Pressure.
At STP: Pressure = 1 bar = 0.987 atm
Temperature = 273 K or 0°C
At NTP: Pressure = 1 atm
Temperature = 293 K or 20°C

Complete Step By Step Solution:
At the same temperature and pressure, equal volumes of all gases contain the same number of molecules. This can be expressed as Avogadro’s Law:
At constant temperature and pressure, the volume occupied by a gas sample is directly proportional to the number of moles of gas. So, V is directly proportional to n.
The volume occupied by a mole of gas at STP is called the standard molar volume and is very nearly a constant for gases. The standard molar volume for an ideal gas is taken to be 22.414 L/mol at STP.
According to Avogadro's hypothesis one gram mole of a gas at NTP occupies 22.4 L.

Hence, the correct option is (b).

Note: Boyle’s Law, Charles Law and Avogadro’s Law can be used to describe the behavior of an ideal gas. An ideal gas is one that obeys these laws strictly. V is inversionally proportional to P,V is directly proportional to T, and V is directly proportional to n
Combining we get: $PV = nRT$
This relationship is called the ideal gas law. R is a proportionality constant called the gas constant and has a value of 8.314 J/mol.