Compounds and Mixtures Name ________________

Elements If a solid, liquid or gas is made up of only one type of atom we say it is an element. For example, consider a tripod made up of iron: These atoms are ALL iron – there’s nothing else in here

Compounds Compounds are different to elements. They contain different types of atoms joined together. Here are some examples: Glucose Methane Sodium chloride (salt)

Some simple compounds… Methane, CH 4 Water, H 2 O Carbon dioxide, CO 2 Ethyne, C 2 H 2 Sulphuric acid, H 2 SO 4 Key Hydrogen Oxygen Carbon Sulphur

Making compounds Compounds are made when two or more elements (or compounds) go through a chemical reaction. For example: 1)When carbon reacts with oxygen it usually forms ________ _________ 2)When oxygen reacts with hydrogen it could form H 2 O (______) 3)When iron reacts with oxygen it could form ______ ______ There are usually “tell-tale” signs to show when a compound is being made, such as bubbling, fizzing, heat given off, colour changes. Words: Water, iron oxide or carbon dioxide

Naming compounds #1 Rule 1 – When two elements join the new compound has a name that ends with ide e.g. Magnesium + oxygen magnesium oxide 1)Sodium and chlorine will make sodium chloride 1)Lithium and hydrogen will make sodium hydride

Naming compounds #2 The first element stays the same but the second element in the compound needs to be changed to have ide added Name of elementhow is it changed oxygenoxide hydrogenhydride nitrogennitride sulphursulphide fluorinefluoride chlorinechloride brominebromide iodineiodide

Naming compounds #3 Fill in the blanks below using the table on the previous slide to help you. Copper and chlorine will make ________ _________ Iron and sulphur will make ________ _________ Magnesium and oxygen will make ________ _________ Calcium and fluorine will make ________ _________ _________ and ________ will make barium nitride

Answers #1 Copper chloride Iron sulphide Magnesium oxide Calcium fluoride Barium and nitrogen 5 correct = 100%

Naming compounds #4 Rule 2 – When three elements join the new compound has a name that ends with ate. One of the elements in an -ate compound is always oxygen. Magnesium, carbon and oxygen makes magnesium carbonate Sodium, sulphur and oxygen makes sodium sulphate Copper, nitrogen and oxygen makes copper nitrate

Naming compounds #5 Fill in the blanks below using the previous slide to help you. Copper, carbon and oxygen will make ________ _________ Lithium, sulphur and oxygen will make ________ _________ Calcium, nitrogen and oxygen will make _______ _________ Potassium, carbon and oxygen will make _______ ________ _______, _______ and _______ will make silver nitrate

Answers #2 Copper carbonate Lithium sulphate Calcium nitrate Potassium carbonate Silver, nitrogen and oxygen 5 correct = 100% You’re a star!!!!

Naming compounds #6 Rule 3 – When three elements join and one of the elements is oxygen, the new compound can have a name that ends with ite. Ite compounds usually have less oxygen in them than ate compounds Magnesium, sulphur and oxygen can join to make magnesium sulphate or magnesium sulphite depending on how much oxygen joins in. Sodium, nitrogen and oxygen can join to make sodium sulphate or sodium sulphite.

Mixtures 100 g 105 g Before After

Element, mixture or compound? Salty waterHydrogen Hydrochloric acid Sodium chloride (salt) Diamond Air

Elements, compounds or mixture #2 Look back at the previous slide and decide whether each of the samples is an element, mixture or compound. Salt water = _____________ Hydrogen = _____________ Hydrochloric acid = _____________ Air = _____________ Diamond = _____________ Salt = _____________

Answers #3 mixture element compound mixture element compound 6 correct = 100%

Air Air is a mixture… Oxygen = 20% Nitrogen = 79% Carbon dioxide Noble gases 79% 21%18% 0.03% 1%

Liquid air Separating air Air can be separated into the different gases that make it up. To do this you first have to cool air down to C and turn it into a liquid: Fractional distillation In this chamber the air is gradually heated up again and the different parts of air “distil” off at different temperatures according to their boiling points Oxygen Argon Nitrogen