Assume that a water balloon has the same number of water molecules as a helium balloon has helium atoms. if the mass of the water is 4.5 times greater than the mass of the helium, how does the mass of a water molecule compare with the mass of a helium atom. explain

Answer : The mass of the water molecule is 4.5 times greater than the mass of the helium atom.

Explanation :

Assumption : The number of water molecules is equal to the number of helium atoms

Given : The mass of water = 4.5 × The mass of helium     (1)

The mass of Water = Mass of 1 water molecule × Number of water molecule

The mass of Helium = Mass of 1 helium atom × Number of helium atom

Now these two masses expression put in the equation (1), we get

Mass of 1 water molecule × Number of water molecule = 4.5 × Mass of 1 helium atom × Number of helium atom

As per assumption, the number of water molecules is equal to the number of helium atoms. The relation between the mass of water molecule and the mass of helium atom is,

Mass of water molecule = 4.5 × Mass of helium atom

Therefore, the mass of the water molecule is 4.5 times greater than the mass of the helium atom.