Gases (Module 20)

Question 1

Define Boyle’s Law

Answer 1

The volume of a fixed mass of gas is inversely proportional to the pressure exerted on it, provided the temperature is constant (PV=Constant)

Question 2

Define The Pressure Law

Answer 2

For a fixed mass of gas at constant volume, the pressure is proportional to temperature (P/T=Constant)

Question 3

Define Charles’ Law

Answer 3

For a fixed mass of gas at constant pressure, the volume of the gas is proportional to temperature. (V/T= Constant)

Question 4

What is the Ideal Gas Equation?

Answer 4

PV/T=constant. From this we can derive the equation PV=NkT (Where K is the boltzmann constant and N is the number of molecules)

Question 5

What Is The Avogadro Constant?

Answer 5

It is the number of atoms in exactly 12g of a carbon isotope. the exact value of this constant is 6.023 x 10^23

Question 6

What Is The Kinetic Theory Equation?

Answer 6

PV=1/3Nm(Crms)^2 (Where Crms is the root mean square speed of the gas molecules)

Question 7

Give Two Assumptions For The Kinetic Model Of Gas

Answer 7

• Elastic collisions between molecules and wall
• Consists of a large number of molecules in random motion
• Gravitational force on molecules is negligible
• No inter-molecular forces (except during collisions)
• Total volume of molecules is negligible compared to the volume of the container