Chemistry Chapter 5

The smallest particle of an element that retains the identity of the element.

A negatively charged particle within the atom.

A particle that is smaller than the atom.

In chemistry, the positively charged centre of the atom.

A positively charged particle that is part of every atomic nucleus.

An uncharged particle that is part of almost every atomic nucleus.

The number of protons in the nucleus of an atom.

The sum of the number of protons and the number of neutrons in the nucleus of an atom.

One or two or more forms of an element that have the same number of protons but a different number of neutrons.

The average mass of the naturally occurring isotopes of an element.

A system for organizing the elements into columns and rows, so that elements with similar properties are in the same column.

Typically, an element that is hard, shiny, malleable, and ductile, and is a good conductor of heat and electricity.

Typically, an element that is not shiny, malleable, or ductile, and is a poor conductor of heat and electricity.

A element that shares some properties with metals and some properties with non-metals.

A horizontal row of elements in the periodic table.

A vertical column of elements in the periodic table.

• (Metal)
• The elements in Group 1. They have low melting points and are soft enough to be cut easily. Highly reactive with water and/or oxygen.

• (Metal)
• The elements in Group 2. Will burn in air if heated and produce bright, colourful flames. Highly reactive but slightly less than Alkali Metal.

• (Non-metal)
• The elements in Group 17. The top of the group (fluorine) to the bottom (iodine), the melting points increase. Highly reactive and extremely corrosive.

• (Non-metal)
• The elements in Group 18. odourless and colourless at room temperature. Non-reactive (stable).

A electron in the outermost occupied level of an atom.