E the given conversion factors below to convert between mass and number of representative par plecules, and ions)
oblem: How many molecules of methane (CHA) if there are 9.65 gram of methane ?

3.63 x 10²³molecules

Explanation:

Given parameters:

Mass of methane = 9.65g

Unknown:

Number of molecules  = ?

Solution:

To solve this problem first, we find the number of moles of the given compound or molecule first.

The given molecule is methane;

    CH₄;

     Number of moles  =

Molar mass of CH₄   = 12 + 4(1)  = 16g/mol

    Number of moles  =   = 0.603moles

So;

From mole concept;

      1 mole of a substance contains 6.02 x 10²³ molecules

    0.603moles of methane will contain 0.603  x  6.02 x 10²³

                                                               = 3.63 x 10²³molecules

b.final