Ontario Grade 9 Science Class Practice Exam

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Master Grade 9 Science with our comprehensive practice exam. Test your knowledge, identify weak areas, and boost your confidence for academic success.

Each practice test/flash card set has 50 randomly selected questions from a bank of over 500. You'll get a new set of questions each time!

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What is an atom?

The smallest unit of an element.
A device used to measure current.
A body that becomes a meteor upon entering Earth's atmosphere.
An element in Group 1 of the periodic table.

The correct answer is: The smallest unit of an element.

An atom is the smallest unit of an element, composed of a central nucleus containing protons and neutrons, surrounded by negatively charged electrons. Option B is incorrect because a device used to measure current is called an ammeter. Option C is incorrect because a meteor is a solid object that enters Earth's atmosphere from outer space. Option D is incorrect because Group 1 elements are alkali metals, a group of elements that share similar chemical properties. Therefore, the correct option is A.