Chemical reactions take place when bonds between atoms are formed, broken, and/or reformed.

Groups of atoms are reformed in chemical changes (reactions) and the Law of Conservation of Matter.

Four states of matter are solid, liquid, gas, and plasma.

The spacing between the particles in a sample and the kinetic energy of the paricles determine the state of matter of a substance.

The temperature of a sample is determined by the kinetic energy of particles.

The movement of and spacing between particles (atoms or molecules) in each of the four states of matter and changes in states of matter.

Mixtures can be separated by physical means whereas compounds must be separated chemically.

Elements are the simplest substances that can be obtained by physical or chemical means.

All the particles in a pure substance are identical and at least one particle is different from the rest in a mixture.

Compare and contrast pure substances (elements and compounds) and mixtures.

Physical properties can be seen and measured whereas chemical properties can only be observed in a chemical change.

Mass and volume are used to determine the density of a substance.

Physical and chemical properties that are used to identify and classify matter.

By the end of the unit, students should demonstrate a clear understanding of the unit’s main ideas and should be able to discuss the following topics: Pure substances, mixtures, elements, and compounds will be investigated while exploring chemical reactions, conservation of matter and the Periodic Table of Elements.

In this unit, students will learn how physical and chemical properties are used to distinguish between different types of matter. Your student’s science class will soon begin exploring a unit entitled “Properties of Matter”.

8th grade matter study guide