making salts test revision

Question 1

what is a…
- solvent
- solute
- solution
- saturated solution

Answer 1

• the liquid in which things are dissolved
• the solid which is being dissolved
• the mixture of solutes dissolved into the solvent
• a solution which contains the max amount of solute which can be dissolved in the solvent

Question 2

what is a base

Answer 2

a substance that accepts H+ ions (from the acid)

Question 3

what types of substances can act as bases

Answer 3

metal carbonates, metal oxides, metal hydroxides and ammonia

Question 4

what are alkalis

Answer 4

bases that are soluble in water

Question 5

describe an experiment to prepare a dry insoluble salt, starting from 2 soluble salts

Answer 5

Use the precipitation method
soluble salt 1 (aq) + soluble salt 2 (aq) –> insoluble salt(s)
+ soluble salt 3 (aq)

react the 2 soluble salts (which are dissolved in water) which leaves a solution with a solid in it. Filter out the solution which leaves just your insoluble salt.

Question 6

describe an experiment starting with an acid and an alkali

Answer 6

Use the titration method
- mix a known volume of alkali with indicator
- using a burette, slowly add acid until the indicator shows that the solution is neutral
- repeat using the known volumes of acid and alkali, but without the indicator
- heat until a saturated solution is formed then leave to form crystals

Question 7

describe an experiment starting with an insoluble reactant

Answer 7

Use the excess base method
- Measure a known volume of acid into a boiling tube and heat in a water bath
- Little by little add the solid base to the hot acid, when the solid stops dissolving, the reaction is complete
- heat until a saturated solution is formed then leave to form crysatls.