If a sample of CO2 contains 48 g of oxygen, how many moles of CO2 are there?

0.75 moles of CO2

Explanation:

molar mass of CO2⇒ 44.01 g/mol

molar mass Oxygen ⇒ 31.998 g/mol

divide the mass given by molar mass of oxygen  so

48÷31.998= 1.50009376 moles of O

then you use the ration of oxygen to carbon to find the moles of CO2 which is one mole of CO2 for 2 moles of oxygen

1.50009376 moles of O × = 0.75004688

with sig figs

0.75 moles of CO2

it's all four options.