Which quantity is held constant when working with boyle’s, charles’s, and gay-lussac’s laws?

The quantity that is held constant when working with Boyle's, Charles's, and Gay-Lussac's laws are moles.

i Just passed the unit test.

The correct answer is the amount of gas or number of moles of gas.

Boyle s law:

Boyle's law describes that at constant temperature and amount of gas, the pressure and volume of gas are inversely proportional to each other.

Charles's law:

It described that at constant pressure and number of moles of gas, the temperature and volume of gas are directly proportional to each other.

Gay-Lussac's law:

According to this law at constant volume and amount of gas, the temperature and pressure are directly proportional.

Hence according to above described 3 laws, the moles or mount of gas remains constant.

the temperature of the gas, in k, not celsius.