Question

Which among the following has more number of molecule 1g of H2 or 1g of methane? Atomic Mass of H=1u and C=12u

Answer 1

To find the number of molecules in a substance, we use Avagadro's constant.

Avagadro's constant states that in every 1 mole of any substance that is in existence, has exactly 6.022 × 10²³ molecules or atoms.

Therefore calculate the moles in each of these two compounds: 

Mole  =  mass/molar mass

Moles of H₂ 

molar mass of H₂ = 2

moles = 1g/2g/mol = 0.5 moles

Moles of methane:

molar mass of methane(CH₄) = 16

moles = 1g/16gmol⁻   = 0.0625

Find the number of molecules in each molecule of these gases using their moles:

                        H₂ =  1 mole is 6.022 x 10²²
                                  0.25 moles = 0.25 moles x  6.022 x 10²³ 
                                                    = 1.50575 x 10²³

That means there are 1.50575 x 10²³  hydrogen molecules in 1 g of hydrogen gas.

Number of molecules is 1g of methane:

1 mole of CH₄ has 6.022 x 10²³ molecules

Therefore 0.0625 moles will have  = 0.0625 x 6.022 x 10²³   molecules
                                                      = 3.764375 x 10²²
There in 1g of methane there are 3.764375 x 10²² methane molecules 

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Therefore 1g of H₂ gas has more molecules than 1 g of methane gas. 

Answer 2

Answer:

1 g of H2 has more no.of molecules