insoluble salts and precipitation reactions

Question 1

steps of insouble salts

Answer 1

removed by filtration
washed with distilled water to remove soluble impurities
dried on filter paper

Question 2

what is a spectator ion

Answer 2

oxidation number

or state doesnt change

Question 3

gravitational filtration

Answer 3

equpiment:
fliter paper( residue in it)
beaker( filtrate in it)
filter funnel

used when small amounts of solid are formed.

Question 4

how are insoluble salts made?

Answer 4

by mixing appropraite soloutions of ions so that a precipitate is formed.
example
barium nitrate and sodium sulphate make
barium sulphate and sodium nitrate

Question 5

vacuum filtration

Answer 5

equpiment:
filter paper
air outlet to water pump
buchner tunnel
buchner
flask (thick glass walls to cope with  vacuum)

apparatus is connected to a water pump, which produces a vacuum.
used if large amounts of solids are formed.

Question 6

precipation reactions.

state example.

Answer 6

full:
Ba(NO3)2 + Na2SO4 -> BaSO4 + 2NaNO3

seperate into ions:
Ba2+ + 2NO3- + 2Na+ SO42- -> BaSO4 + 2Na+ + 2NO3

cancel out spectator ions:
Ba2+ + 2NO3- +SO42- -> BaSO4