Question

which of the following represent compounds? select all that apply a o₂ b co₂ c cl₂ d nacl

Explanation:

Step1: Recall compound definition

A compound is a substance made up of two or more different - element types.

Step2: Analyze each option

• $O_2$ is made up of only oxygen atoms, so it is an element (a di - atomic molecule of the same element).
• $CO_2$ is made up of carbon and oxygen atoms, so it is a compound.
• $Cl_2$ is made up of only chlorine atoms, so it is an element (a di - atomic molecule of the same element).
• $NaCl$ is made up of sodium and chlorine atoms, so it is a compound.

Answer:

b. $CO_2$, d. $NaCl$