An organic compound was found to contain 10% hydrogen and 90% carbon by mass. Find its empirical formula​

Let's take 100 g of this compound;

Quantity of hydrogen (mol) = (100*0.1)/1 = 10,

Quantity of carbon (mol) = (100*0.9)/12 = 7.5,

simple formula - C7.5H10->multiply by 10, so empirical formula is C75H100.