Chemistry

What is matter?

Anything that has mass and occupies space (volume); composed of atoms & molecules)

What is matter classified as?

Pure Substances and Mixtures

What are pure substances?

Substances made of only one type of atom or only one type of molecule

What are mixtures?

Substances that are composed of different types of atoms or molecules that are not chemically bonded

_____ can be separated by physical mean, while _____ cannot

Mixtures, Pure Substances

What 2 things are classified as pure substances?

Elements and Compounds

What are elements?

Pure substances made of one type of atom

What are compounds?

Pure substances made of two or more types of atoms bonded together

What are the 2 types of mixtures?

Heterogeneosu and Homogeneous mixtures

What are heterogeneous mixtures?

Combinations of two or more substances that remain distinct and can be easily separated. (the components do not blend uniformly)

What are homogeneous mixtures?

Composed of solid, liquid or gaseous molecules that are evenly distributed and has the same proportions of its components throughout any given sample

What are the processes of separating mixtures?

1. Filtration - separating solids from liquids using a filter.

2. Distillation - separating liquids based on boiling points.

3. Evaporation - removing a liquid to leave solid residues.

4. Magnetism - using magnets to separate magnetic materials from non-magnetic ones.

What is the difference between a physical and chemical change?

A physical change is when physical appearances changes, while a chemical change is when bods are broken or formed

What are 4 evidences of a chemical change?

• Precipitate forms

• Change in color

• Production of gas (bubbles)

• Heat released/absorbed

How does matter phase change?

Matter will undergo phase change when the temperature and pressure cause molecules to separate further apart or closer together

Why is phase change not a chemical change, but a physical?

No bonds are broken or found, only intermolecular forces of attraction

Combustion reaction

When hydrogen reacts with excess oxygen gas to produce carbon dioxide and water vapor

What is Nuclear fusion?

The process where two small nuclei combine to form a bigger nucleus, releasing a significant amount of energy

What is nuclear fission

The process in which the nucleus of an atom splits into two or more smaller nuclei, along with the release of energy.