Among the four quantities-mass, pressure, temperature and volume, which are taken to be constant in the following gas laws?
(i) Boyle's law,
(ii) Charles' law
(iii) Gay-Lussac's law
(iv) Avogadro's law.

Explanation

(i) Boyle's law: Mass and temperature of the gas.
(ii) Charles's law: Mass and pressure of the gas.
(iii) Gay-Lussac's law: Mass and volume of the gas.
(iv) Avogadro's law: Pressure and temperature of the gas.