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What is the scientific method?

A systematic approach to inquiry that involves observation, hypothesis formulation, experimentation, and conclusion.

What are the three states of matter?

Solid, liquid, and gas.

What is the formula for calculating the area of a circle?

$A = ext{pi} imes r^2$, where $r$ is the radius.

What is photosynthesis?

The process by which green plants use sunlight to synthesize foods from carbon dioxide and water.

What is Newton's First Law of Motion?

An object at rest stays at rest and an object in motion stays in motion at a constant speed unless acted upon by a net force.

What is the pH scale?

A scale that measures how acidic or basic a solution is, ranging from 0 to 14.

What is osmosis?

The movement of water molecules across a semi-permeable membrane from an area of low solute concentration to an area of high solute concentration.

What is the atomic number of an element?

The number of protons in the nucleus of an atom, which determines the element's identity.

What is a chemical reaction?

A process that leads to the transformation of one set of chemical substances to another.

What is the law of conservation of mass?

Mass is neither created nor destroyed in a chemical reaction.