Question

Empirical formula of ch2 and molar formula of 56 grams what is molecular formula

Answer 1

One mole of carbon weighs 12 grams and one mole of hydrogen weighs 1 gram. Therefore, one mole of CH2 weighs 12 + 1 + 1 = 14 grams.

56 divided by 14 = 4

Therefore, you need 4 "moles" of CH2 to equal 56 grams of the unknown substance. To get the equivalent of 4 "moles" of CH2 you need one mole of C4H8.


Hope this helps :)

Answer 2

To find the molecular formula from the empirical formula, you need to find a multiple (x) that will give you the molar mass of the compound which in the question is 56 g/mol.

If CH₂ is the empirical formula
 molar mass of empirical formula = (12 × 1) + (1 × 2) g/mol
                                                     =  14 g/mol
let x = multiple
let molecular formula = Cₓ H₂ₓ

            multiple = molecular mass ÷ empirical mass
                         =  56 g/mol ÷  14 g/mol
                         =  4


If molecular formula = Cₓ H₂ₓ
then molecular formula = C₄H₂₍₄₎
                                      = C₄H₈