Question

______ are substances with constant composition that are made of elements chemically bonded to each other.
options: solutions, mixtures, compounds, quarks, heterogeneous mixtures

Explanation:

To solve this, we analyze each option:

• Solutions: Homogeneous mixtures, not constant composition from bonded elements.
• Mixtures: Variable composition, not chemically bonded elements.
• Compounds: Substances with constant composition, formed by elements chemically bonded.
• Quarks: Subatomic particles, not substances with element bonding.
• Heterogeneous mixtures: Variable composition, not bonded elements.

So the correct option is Compounds.

Answer:

C. Compounds