Answer:
Pressure is inversely proportional to the volume of gas.
Explanation:
According to Boyle's law,
The volume of given amount of gas is inversely proportional to the pressure applied on gas at constant volume and number of moles of gas.
Mathematical expression:
P ∝ 1/ V
P = K/V
PV = K
when volume is changed from V1 to V2 and pressure from P1 to P2 then expression will be.
P1V1 = K P2V2 = K
P1V1 = P2V2
Answer:

Explanation:
A pressure of 1 atm and a temperature of 0 °C is the old definition of STP. Under these conditions, 1 mol of a gas occupies 22.4 L.
1. Calculate the moles of hydrogen.

2. Calculate the number of molecules

Answer:
Because X-rays have wavelengths similar to the size of atoms