Ohne Titel

Seite 1

Particle Theory

1. All matter is made up of small particles

2. All particles of a pure substance are identical to each other and different from another pure substance

3. All particles are constantly moving

4. Particles attract one another

5. Particles at higher temperature (more energy) move faster than particles at a lower temperature

6. All particles have space between them.

Bohr- Rutherford Model

1. Atoms are very small

2. The mass of the electron is extremely small compared to the mass of the entire atom

3. The electrons exist in energy levels outside the nucleus.

4. Atoms are made of charged particles that can be separated from each other to form ions

5. The identity of an element is determined by the number of protons in the nucleus

6. Atoms of the same element can differ only in the number of neutrons in the nucleus

Physical and Chemical Changes

Physical Change- in a physical change the substance stays the same but may change shape or state

Chemical Change- in a chemical change the original substance is changed into one or more different substances that have different properties. It is very difficult to reverse a chemical change

Signs that a chemical change has occurred

1. A new colour appears

2. Heat or light given off

3. Bubbles of gas form

4. A new substance was formed

eg. Iron Rusting, Cake Baking, Match Burning

Chemical Families

Alkali Metals

Alkaline Earth Metals

Halogens

Noble Gases

P.D.M

Protons Don't Move

Bohr Diagrams

Ions

Metals always loose electrons (+)

Non- Metals always gain electrons (-)

Isotopes

Isotopes- each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei,

Anions & Cations

Anions (-)

Cation (+)

Ion

An atom or molecule with a net electric charge due to the loss or gain of one or more electrons.

Reactants & Products

Products are the results of the chemical reaction. They appear on the right side of the equation. Reactants, on the other hand, are the starting points of the chemical reaction. They appear on the left side of the equation.

New Page