Science: Chemistry Grade 8

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Atoms and molecules:

What are atoms?

An atom is the smallest unit of ordinary matter that forms a chemical element. Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are the smallest possible chunks of a pure element.

What are molecules?

A molecule is a group of atoms. They are multiple atoms bonded together. These bonds form as a result of the sharing or exchange of electrons among atoms.

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Elements and compounds:

What is an element?

Elements are pure types of material like Hydrogen (H) and Oxygen (O).

What is a compound?

Compounds are combinations of multiple elements like water (H2O), carbon dioxide (CO2 ), baking soda (NaHCO3).

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