salt preparation

Question 1

what are all soluble salts?

Answer 1

all sodium + potassium + ammonium + nitrate salts

Question 2

which salts are all soluble except for lead (ii) and silver?

Answer 2

chloride + bromide + iodide salts

Question 3

what sulfate salts are insoluble?

Answer 3

barium + lead (ii) + calcium

Question 4

what are the only carbonates that are soluble?

Answer 4

group1 metals + ammonium carbonates

Question 5

what are the only hydroxides that are soluble?

Answer 5

group 1 + calcium + barium hydroxides/oxides

Question 6

what is the only soluble lead compound?

Answer 6

lead (ii) nitrate

Question 7

how do you make an insoluble salt?

Answer 7

precipitation

Question 8

how do you make a soluble salt with a soluble base/carbonate?

Answer 8

titration

Question 9

how do you make a soluble salt with an insoluble base/carbonate?

Answer 9

reaction of acid with excess insoluble bcm

Question 10

what is a precipitate?

Answer 10

a solid that forms in a solution

Question 11

what conditions must be met to form a precipitate?

Answer 11

both reactants must be in aqueous solution + products must be insoluble in water

Question 12

what is the equation that represents the precipitation method?

Answer 12

AB (aq) + CD (aq) -> AD (s) + CB (aq)

Question 13

what do you do if the starting reagent is an insoluble substance?

Answer 13

be converted into a soluble salt before the precipitation react can take place

Question 14

what are the two reactions that can be expected from the titration method?

Answer 14

acid + alkali -> salt + water
acid + carbonate -> salt + carbon dioxide + water

Question 15

what kind of salts are produced by titration?

Answer 15

salts of very reactive metals + ammonium

Question 16

what are the conditions to be met for titration to be used?

Answer 16

both reactants are soluble and both products are soluble

Question 17

why is an indicator used for titration?

Answer 17

there is no visible residue/undissolved solid reactants to indicate a complete reaction which may allow the salt to be contaminated with excess acid/base/carbonate

Question 18

on a pH graph, what is the point called where the pH reaches 7?

Answer 18

equivalence point

Question 19

what are the three reactions for reaction of acid with excess insoluble bcm?

Answer 19

acid + excess metal -> salt + hydrogen
acid + excess insoluble base -> salt + water
acid + excess onsoluble carbonatre -> salt + water + carbon dioxide

Question 20

why is excess of the bcm added to the acid?

Answer 20

to ensure that all the sulfuric acid will be used up and prevents the salt solution will be contaminated with the acid

Question 21

why is the mixture filtered?

Answer 21

to remove excess bcm

Question 22

why is the mixture heated to about half or one-third its original volume?

Answer 22

to form a saturated solution for crystallization to occur

Question 23

why is crystallization is used as opposed to heating to dryness?

Answer 23

heating to dryness would cause the salt to lose the water of crystallization

Question 24

why are the crystals wash with cold distilled water?

Answer 24

so it does not dissolve crystals but is able to remove soluble impurities

Question 25

why are crystals dried between sheets of filter paper?

Answer 25

prevent the loss of water of crystallisation

Question 26

what type of salts are made from reaction of acid with base or metal carbonate?

Answer 26

moderately reactive metals and unreactive metals