Question

identify all of the items that represent an element and not a molecule. select all that apply
□ cao
□ h
□ li
□ ne
□ co₂
□ n₂

Explanation:

Step1: Recall element and molecule definitions

An element is a pure substance made of only one - type of atom. A molecule is made of two or more atoms chemically bonded together.

Step2: Analyze each option

• $CaO$: It is a compound made of calcium ($Ca$) and oxygen ($O$) atoms, so it is a molecule, not an element.
• $H$: Represents the hydrogen element. It is a single - atom symbol of an element.
• $Li$: Represents the lithium element. It is a single - atom symbol of an element.
• $Ne$: Represents the neon element. It is a single - atom symbol of an element.
• $CO_2$: It is a compound made of carbon ($C$) and oxygen ($O$) atoms, so it is a molecule, not an element.
• $N_2$: It is a molecule as it is made of two nitrogen atoms bonded together.

Answer:

H, Li, Ne