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

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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 :)
User Tim Penner
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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




User Yusuf X
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