Final answer:
After converting the given masses to moles, the empirical formula is determined by finding the simplest whole-number ratio of carbon to hydrogen atoms, which is CH3.
Step-by-step explanation:
To determine the empirical formula for a compound that contains 7.00 g of carbon and 1.75 g of hydrogen, we first convert these masses to moles by using the molar masses of carbon (12.01 g/mol) and hydrogen (1.008 g/mol). For carbon, 7.00 g ÷ 12.01 g/mol = 0.583 moles, and for hydrogen, 1.75 g ÷ 1.008 g/mol = 1.736 moles. The empirical formula is the simplest whole number ratio of atoms in a compound, so we divide the moles of each element by the smallest number of moles, which is 0.583 in this case, yielding: C (0.583 moles ÷ 0.583) = 1 and H (1.736 moles ÷ 0.583) = 2.98, which approximates to 3 when rounded to the nearest whole number. Therefore, the empirical formula is CH3.