Did you know that there are 4 ways of making salt? cgrahamphysics.com

Transcription

1 Did you know that there are 4 ways of making salt?

2 Starter

3 1. Recap methods of making and naming salts. 2. Recap the term 'NeutralizaBon' and indicators. 3. Make your own salt through pracbcal method.

4 The chemical reacbon between an acid and an alkali is called neutraliza*on. What is the ph value of the mixture of salt and water? acid alkali salt water The mixture of salt and water is neutral, so its ph is 7. The chemical reacbon between an acid and an alkali can be wriken as: acid alkali salt water

5 The salt produced by a neutralizabon reacbon depends on the acid and the alkali used. Sodium chloride is produced by the reacbon between hydrochloric acid and sodium hydroxide. hydrochloric acid sodium sodium hydroxide chloride water Which acid and which alkali would be needed to make the salt potassium chloride? hydrochloric acid potassium hydroxide potassium chloride water

6 Naming salts l When an alkali reacts with hydrochloric acid, the salt produced is a chloride. l When an alkali reacts with sulfuric acid, the salt produced is a sulfate. l When an alkali reacts with nitric acid, the salt produced is a nitrate. Which acid would be needed to make these salts? 1. copper nitrate 2. magnesium chloride 3. sodium sulfate

7 When an acid reacts with a base, a neutraliza*on reacbon occurs and produces a chemical called a salt. acid base salt water The name of the salt depends on the names of the reactants. l The first part of the salt s name comes from the base: e.g. sodium hydroxide sodium l The second part of the salt s name comes from the acid: e.g. sulfuric acid sulfate For example, if sodium hydroxide neutralizes sulfuric acid, the product is a salt called sodium sulfate.

8 Acid alkali à metal salt water Complete these word equabons: hydrochloric acid potassium hydroxide potassium chloride water sodium hydroxide sulfuric acid sodium sulfate water potassium nitric acid hydroxide potassiumnitrate water

9 Second way When a carbonate is mixed with an acid, the products are a salt, carbon dioxide and water. acid carbonate salt water carbon dioxide For example: nitric acid copper carbonate copper water nitrate carbon dioxide Third way When a metal is mixed with an acid, the products are a salt, and hydrogen gas. nitric acid copper copper nitrate hydrogen

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12 Fourth way Add 20 cm3 of the 0.5 M sulfuric acid to the 100 cm3 beaker. Heat carefully on the tripod with a gentle blue flame. Don t boil or you will release toxic fumes When the acid is hot enough (just before it starts to boil), use a spatula to add small porbons of copper(ii) oxide to the beaker. SBr the mixture gently for up to half a minute a]er each addibon. Add excess copper oxide unbl no more can be dissolved Allow the beaker to cool slightly while you set up Stage 2.

13 Place the filter funnel in the neck of the conical flask. Fold the filter paper to fit the filter funnel, and put it in the funnel. Make sure the beaker is cool enough to hold at the top. The contents should sbll be warm. Gently swirl the contents to mix, and then pour into the filter paper in the funnel. Allow to filter through. A clear blue solubon should collect in the flask. If the solubon is not clear, and black powder remains in it, you will need to repeat the filtrabon. It is wise to check (using ph paper) that no acid remains.

14 Pour the solubon in an evaporabon basin. Gently evaporate ½ of the liquid. Set on the windowsill to cool

15 Write the general equabon for reacbng an acid and alkali. This type of reacbon is know as a ReacBon. Sulphuric acid Sodium Hydroxide à? Chlorides are made from which acid? Nitrates are made from which acid? Sulphates are made from which acid? Citrates are made from which acid? Write down the 4 ways of making salt