The greater the mass of an object the greater its volume true or false

TRUE

Explanation:

Density  = Mass / Volume

Rearranging the formula

Volume = Mass / Density

So we see here volume is directly proportional to its mass.

Mass is the amount of matter present in a substance  

Volume is the space occupied by a substance.

As per Avagadro’s law  

At constant temperature and pressure, the volume occupied by a gas is directly proportional to the number of moles of the gas.

Directly proportional means when one increases the other one too will increase. That is, Equal volume of different gases will have the same number of moles at constant temperature and pressure.  

1 mole of Hydrogen gas at T = 273K and P = 1 atm occupies a volume of 22.4L

1 mole of Argon gas at T = 273K and P = 1 atm occupies a volume of 22.4L

This is given by the expression  

(at constant temperature and pressure)

Introducing a constant we have  

V / n = k

Where V is the volume, n is the number of moles and k represents a constant.

When there is a change in volume or number of moles we make use of the expression  

As volume increases, the number of moles occupies too will increase.  

Moles is related to mass by the formula  

Moles = Mass / Molarmass

So volume, moles and mass are all directly proportional to each other