Chemistry

Atomic structure

All substances are made from tiny particles called atoms. An atom has a small central nucleus made up of smaller sub-atomic particles called protons and neutrons. The nucleus is surrounded by even smaller sub-atomic particles called electrons.

1 of 28

Atomic number

The atomic number of an atom is the number of protons it contains. All the atoms of a particular element have the same atomic number (number of protons)

2 of 28

mass number

The mass number of an atom is the total number of protons and neutrons it contains. The mass number of an atom is never smaller than the atomic number. It can be the same, but is usually bigger.

3 of 28

Full chemical symbols

You need to be able to calculate the number of each sub-atomic particle in an atom if you are given its atomic number and its mass number. The full chemical symbol for an element shows its mass number at the top, and its atomic number at the bottom.

4 of 28

Electronic structure

The electrons in an atom occupy energy levels. These are also called shells. Each electron in an atom is found in a particular energy level. The lowest energy level (innermost shell) fills with electrons first. Each energy level can only hold a certa

5 of 28

Ionic bonds

Chemical bonds involve electrons from the reacting atoms. Compounds formed from metals and non-metals consist of ions. Ions are charged particles that form when atoms (or clusters of atoms) lose or gain electrons:

6 of 28

Covalent bonds

Compounds formed from non-metals consist of molecules. The atoms in a molecule are joined together by covalent bonds. These bonds form when atoms share pairs of electrons.

7 of 28

Thermal decomposition

calcium carbonate>heat>calcium oxide + carbon dioxide

8 of 28

Cement, mortar and concrete

Cement is made by heating powdered limestone with clay. Cement is an ingredient in mortar and concrete: mortar, used to join bricks together, is made by mixing cement with sand and water

9 of 28

transition metals

they are metals, they are good conductors of heat and electricity, they can be hammered or bent into shape easily

10 of 28

Iron

Iron is extracted from iron ore in a huge container called a blast furnace. Iron ores such as haematite contain iron oxide. The oxygen must be removed from the iron oxide to leave the iron behind.

11 of 28

reduction reactions.

Reactions in which oxygen is removed are called

12 of 28

electrolysis.

Electricity is passed through solutions containing copper compounds, such as copper sulfate. During electrolysis, positively charged copper ions move towards the negative electrode and are deposited as copper metal.

13 of 28

phytomining.

Some plants absorb copper compounds through their roots. They concentrate these compounds as a result of this. The plants can be burned to produce an ash that contains the copper compounds

14 of 28

bioleaching.

Some bacteria absorb copper compounds. They then produce solutions called leachates, which contain copper compounds.

15 of 28

Extraction

Unlike iron, aluminium and titanium cannot be extracted from their oxides by reduction with carbon

16 of 28

Alloys

The properties of a metal are changed by adding other elements to it. A mixture of two or more elements, where at least one element is a metal

17 of 28

Alkanes

These are compounds that contain hydrogen and carbon atoms only, joined together by chemical bonds called covalent bonds. There are different types of hydrocarbon, but most of the ones in crude oil are alkanes.

18 of 28

Distillation

Distillation is a process that can be used to separate a pure liquid from a mixture of liquids. It works when the liquids have different boiling points. Distillation is commonly used to separate ethanol (the alcohol in alcoholic drinks) from water.

19 of 28

Fractional distillation

Fractional distillation is different from distillation in that it separates a mixture into a number of different parts, called fractions

20 of 28

Complete combustion

Fuels burn when they react with oxygen in the air. If there is plenty of air, complete combustion happens. Coal is mostly carbon. During complete combustion, carbon is oxidised to carbon dioxide:

21 of 28

Incomplete combustion

If there is insufficient air for complete combustion, incomplete combustion (also called partial combustion) happens. Hydrogen is still oxidised to water, but carbon monoxide forms instead of carbon dioxide. Carbon monoxide is a toxic gas, so adequat

22 of 28

Biofuels,Biodiesel

are fuels produced from plant material, Biodiesel is made from rapeseed oil and other plant oils.

23 of 28

Bioethanol

it is a liquid fuel that burns well. Bioethanol is made by fermenting sugars from sugar cane, wheat and other plants. It cannot be used on its own unless the engine is modified.

24 of 28

Cracking

Cracking allows large hydrocarbon molecules to be broken down into smaller, more useful hydrocarbon molecules. Fractions containing large hydrocarbon molecules are heated to vaporise them.

25 of 28

Alkenes

The products of cracking include alkenes (for example ethene and propene). The alkenes are a family of hydrocarbons that share the same general formula

26 of 28

Monomers and polymers

Alkenes can be used to make polymers. Polymers are very large molecules made when many smaller molecules join together, end-to-end. The smaller molecules are called monomers.

27 of 28

Plate tectonics

The Earth's crust and upper part of the mantle are broken into large pieces called tectonic plates. These are constantly moving at a few centimetres each year. Although this doesn't sound like very much,

28 of 28

Get Revising

Chemistry

Other cards in this set

Card 2

Front

Back

Card 3

Front

Back

Card 4

Front

Back

Card 5

Front

Back

Comments

Similar Chemistry resources:

Other cards in this set

Card 2

Front

Back

Card 3

Front

Back

Card 4

Front

Back

Card 5

Front

Back

Comments

Related discussions on The Student Room

Similar Chemistry resources: