Preparing Salts

Question 1

What are four uses of salts? (4 points)

Answer 1

• colour of fireworks are formed when certain salts burn (strontium chloride= burn bright red colour)
• table salt is sodium chloride
• indigestion remedies (often contain magnesium salts)
• salts can be used as coloured pigments in paints+ help fuels burn better

Question 2

What is the REDOX reaction used to make salts?

Answer 2

Metal + acid —-> salt + hydrogen

Question 3

What is the formula for the salts we can make using insoluble bases to NEUTRALISE acids? (2)

Answer 3

• metal oxide + acid ——> salt + water
• metal carbonate + acid ——> salt + water + carbon dioxide

Question 4

What is the FIRST STEP in the method of making pure, dry crystals of POTASSIUM CHLORIDE?

Answer 4

1- add 25 cm cubed hydrochloric Acid to a beaker and heat gently

Question 5

What is the SECOND STEP in the method to make pure, dry crystals of potassium chloride?

Answer 5

2- Add potassium oxide, a spatula at a time, stirring regularly

Question 6

What is the THIRD STEP in the method to make pure, dry crystals of potassium chloride?

Answer 6

3- Stop adding the potassium oxide when it begins to sink to the bottom of the beaker + no longer reacts with acid

Question 7

What is the fourth step in the method to make pure, dry crystals of potassium chloride?

Answer 7

4- filter the solution using a filter funnel and paper to remove the EXCESS OXIDE

Question 8

What is the FIFTH STEP to make pure, dry crystals of potassium chloride?

Answer 8

5- Heat the solution of potassium chloride using an electric heater or drying oven to EVAPORATE the water+ get crystals

Question 9

What is the SIXTH STEP in the method to make pure, dry crystals of potassium chloride?

Answer 9

6- Pat the crystals dry using filter paper