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What is a horizontal row and vertical row in periodic table called

Horizontal rows are called periods
Vertical columns are called groups

What does each group show?

Elements within the same group have similar chemical properties.
elements in the same group have the same number of electrons in their outer shell 

What does each period show?

Elements in the same period have the same number of shells.

Who created the Periodic table?

Dimitri Mendeleev created it in the mid 19th century and even left gaps for elements that were not discovered yet

When does a covalent bond occur?

When a molecule consists of 2 or more non-metal atoms.
A covalent bond is formed when a PAIR of electrons is shared between 2 atoms.

Properties of a simple molecular substance

Have low melting and boiling points
Usually gases or liquids at room temperature
Weak intermolecular forces between molecules
Can’t conduct electricity

Define Giant covalent structure

covalent substances with millions of atoms are called giant covalent structures (eg. diamonds and graphite)
High melting and boiling points

Properties of Diamond

Made of carbon and all 4 outer electrons form a covalent bond
Do not conduct electricity (no free electrons)
High melting and boiling points (high energy needed to break covalent bonds)
Hard Substance (strong covalent bonds)

Properties of graphite

Made of carbon atoms (3 of 4 outer electrons are covalently bonded)
Good electrical conductor (has delocalised electrons)
High melting and boiling point
Soft layers can slide over one another (weak intermolecular forces between layers)

General properties of metals

Solid at room temperature
high melting point
good conductors of electricity and heat
malleable and ductile
strong and dense

Properties of ionic compounds

High melting and boiling points
Conduct electricity when liquid (melted or dissolved)
High strength bonds

Define ionic compound

Ionic structures involve many ions bonded together via ionic bonds. The solid arranges itself into a regular 3D structure known as a lattice.

Why can ionic compounds only conduct electricity when in liquid/molten, or aqueous form?

To conduct electricity, it must have charged particles, that are free to flow through the structure. 

When is a metallic bond formed?

When a metal binds to another metal, a metallic bond is formed.

How do metals conduct heat and electricity

In metallic bonding, electrons delocalised from lattice of metal ions. 
These electrons can carry charge, and so metal acts as a conductor of electricity. 
These electrons can also carry thermal energy, meaning metals are good conductors of heat.

Why are metals strong?

When a metal is hit, the layers of metal ions are able to slide over each other so the structure can not shatter. The metallic bonds don’t break because electrons are free to move throughout the structure

Average size of a nanoparticle

Nanoparticles are 1-100nm in size
1nm = 1×10^(-9)m

What is the most common use of nanoparticles

Most commonly used as catalysts to speed up chemical reactions.
Due to their larger surface area to volume ratio.
Catalyse reactions more efficiently, catalyse different reactions and produce more products

Risks of Nanoparticles

People concerned the small size makes it possible to breathe them in or for them to pass into cells. Inside the body, they may catalyse harmful reactions
Toxic substances may bind to them due to large surface area to volume ratios, harming health

What are polymers

Polymers- large molecules formed from many identical smaller molecules known as monomers

Definition of Compound, mixture and molecule

Mixture- contains two or more substances that are not chemically combined.
Compounds- a substance made from two or more different elements that are chemically bonded together
Molecule- group of two or more than two atoms of the same or different elements that are chemically bonded together

Steps of simple distillation

A solution is heated, usually using a Bunsen burner.
The liquid in the mixture evaporates into a gas. 
The gas is cooled by a water jacket and condenses into a liquid, which then flows into the beaker. 

What is the use of distillation

Used to separate a pure liquid from a mixture of liquids or solid. Works when liquids or dissolved solute have different boiling points.

What is the use of filtration?

Used to separate an insoluble solid from liquid

Describe process of filtration

One beaker contains a mixture of insoluble solid and liquid, the other contains a funnel with filter paper
The solid and liquid mixture is poured into the filter funnel
The liquid or solution drips through the filter paper but the insoluble solid particles are caught in filter paper