Question

7. A flask of methane (CH4) was weighed. Methane was then pushed out and the flask again
weighed when filled with oxygen at the same temperature and pressure. The mass of oxygen
would be
(A) The same as the methane
(B) Half of the methane
(C) Double of that of methane
(D) Negligible in comparison to that of methane​

Answer 1

Answer:

A)The same as Methane.

Answer 2

Answer:

We know that the Avogadro's law states that the "equal volumes of any two gases at the same temperature and pressure contain the same number of molecules".

So, by equating the number of moles we will get that:

Weight of CH4/molar mass of CH4 = Weight of O2/molar mass of O2.

Then, the ratios of the masses which is molar mass of O2/molar mass of CH4

will be equal to 32/16 = 2.

So, the mass of the oxygen will be 2 times or double that of methane or CH4.