Sec 4 - Chapter 1 - Atoms amd Elements

His Gold Foil Experiment showed an atom is mostly empty space, contains a positive very dense and very small nucleus.

He updated Rutherford’s model: protons and neutrons are in the nucleus, electrons are in orbitals

Poor conductors of heat and electricity Many are gases at room temperature The solids can be easily made into powder.

The repetition of patterns in the properties from one period to another

Boiling Point –Temperature at which a liquid becomes a gas 

The elements in group 2. Highly malleable, reactive, burn easily

Dalton's atomic theory has four main points: all matter is composed of tiny, indivisible particles called atoms, ......

Gamma (γ) – negatively charged

The model!!

They are good conductors of heat and electricity, ductile, malleable, shiny, solids at room temp, react with acid.

Alpha (α) – positively charged

In neutral atoms the number of electrons is equal to the number of neutrons. 

One of the particles that make up an atom. It is negatively charged

1 mole = 3.02 X 10²³ 

The model!!

There are 7 elements with properties of both metals and non-metals

He believed the atom was made of tiny indivisible particles called atoms. His model is the discontinuous model.

It is the number of protons found in the nucleus

Ernest Rutherford designed the current periodic table.

Group 8 -Very stable

The sum of the protons and the neutrons in an atom

Group 7 -Non-metals, react easily to form compounds, several are powerful disinfectants

An atom with the same number of protons as another atom but a different number of neutrons

Holds the protons together. Have no charge

The periodic table organizes the elements according to their physical and chemical properties.

He believed matter was infinitely divisible. Said matter was continuous.

One of the particles that makes up an atom. It is found in the nucleus and carries a positive charge

An atom is mostly empty space, contains a very dense and very small nucleus and the nucleus has a positive charge

Atoms are positively charged ball embedded with small negatively charged particles called electrons. Plum Pudding Model!

The model!!!

Avogadro's number is the number of particles in one mole of a substance

Is the smallest particle of matter. It cannot be divided chemically.

Soft, highly reactive metals found in group 1. Stored in oil because they react with water.