The number of organic compounds among the following is:

Urea, Carbon tetrachloride, Carbon dioxide, carbon monoxide, Sodium carbonate.

Only urea and carbon tetrachloride are organic compounds.

Urea (NH₂-CO-NH₂) is an organic compound found in animal urine and also contains a carbonyl group as a functional group. Similarly, carbon tetrachloride (CCl₄) is also formed by the substitution reaction of methane. So, it is also an organic compound.

Carbon dioxide and carbon monoxide are found in the atmosphere and are not obtained from living organisms. So they are inorganic compounds.

As sodium carbonate(Na₂CO₃) is a mineral and not obtained from living organisms, it is also nor an organic compound.