Question

A compound with a molar mass of 84 g is composed of 85.7% carbon and

14.3% hydrogen by mass. What is its molecular formula?

Answer 1

first you draw a table as I've drawn.

Since moles = mass÷RAM

divide the element with the lowest ram to it self and the other element to find ratio..

Then to the unknown number[n] Multiply it to the formula C H2 and equate it to 84..

n will be 6 hence C6 H12