SCIENCE TEST

Atom

Is the fundermental building block of all matter

Molecular

A cluster of atoms that make up an element or compound

Crystal lattice

Gridlike like structure of atoms or ions bonded to all of its neighbouring atoms

What makes up atoms (sub-atomic particles)

Protons, neutrons, electrons

Overall charge of an atom

Neutral charge

Charge of a nucleus in an atom

Positively charged

Electrostatic attraction

The force of attraction is between two oppositely charged particles

Occurs between protons and electrons

Electrostatic repulsion

The force between particles that have the same charge

Occurs between protons and in the nucleus

Isotope

An atom that has the same number of protons but different number of neutrons

Electron configuration

The way in which electrons are arranged in shells/orbit around the nucleus

Negative ions form when

When a neutral atom gains electrons so it has more electrons and protons

Positive ions from when

When a neutral atom loss electrons, so it has more protons and electrons

Solubility

The ability for a given substance, the solution, to dissolve in a solvent

Valency

The charge of an ion

Polyatomic ions

Is a ion that contains more than one atom

Elements, e.g.

Substance that are made up of only one type of atom e.g. diamonds, gold

Ions

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

Three physical properties of metals

Lustrous, malleable, ductile, conducts electricity, conducts heat, dense, solid at room temperature

Alloy

Is a metal (base metal) combined with small amounts of other elements (metal or non-metal)

Non-metals

Allotrope e.g.

Is a pure element in different forms e.g. carbon

What are metalloids

Elements that acts like non-metals but have some elements like metals

What are metalloids use for

They can conduct electricity in certain conditions and are called semi-conductors

Acid e.g.

A substance that releases hydrogen ions into aqueous solutions e.g. hydrochloride acid

Three properties of acids

Corrosive, sour taste, turns blue in litmus paper red, reacts with some metals, conducts electricity,neutristed by bases

What is a base

A substance that releases hydroxide into solution

Alkali

A base that is dissolved in water forms and alkaline solution

Three properties of bases

Caustic, have a soapy, slimy feel, bitter in taste, conducts electricity, and neutralised by acids

What is the pH scale used to measure

Concentration of H ions(H+)

In acidic solution

There are more H+ ions then 0H- ions

In alkaline solutions

There are more 0H- ions then H+ ions