In an experiment, a 2.514 g sample of calcium is heated in oxygen and the compound formed has a mass of 3.518 g. What is the empirical formula for the compound?

1 Answer
Jan 20, 2017

We get an empirical formula of CaO.

Explanation:

We can work out the individual masses of the elements in the binary compound, and we convert this to a molar quantity of each element:

Moles of calcium = 2.514g40.1gmol1=0.0627mol

Moles of oxygen = 3.518g2.514g16.00gmol1=0.0627mol

We divide thru by the smallest molar quantity, and since there are equimolar quantities of metal and oxygen, the empirical formula is:

CaO.