Question

What is the empirical formula of a substance that consists of 3.664 g calcium, 2.561 g nitrogen, and 8.775 g oxygen?

Show the step on how will u get the answer. thanks

A. CaNO

B. Ca₂NO₇

C. CaN₂O₄

D. CaN₂O₆

Answer 1

The formula which represents the simple ratio of the atoms of two different elements in one molecule of the substance is called empirical formula.

Example C₂H₆ empirical formula is CH₃

From the data

Element	Ca	N	O
Mass	3.664g	2.561g	8.775g
Molecular weight	40g/mole	14g/mole	16g/mole
Number of moles (weight/ M.Wt.)	= 0.0916mol	= 0.1829mol	= 0.5484mol
Simple mole ratio (divide each with small number mole ratio)	= 1	= 2	= 6
Number of atoms	1	2	6
Therefore	1 Ca	2 N	6 O

In the given compound, 1 Ca atom, 2 N atoms and 6 O atoms so

Empirical formula of is CaN₂O₆

answer D.