preserving metals

Question 1

ferrous metals

Answer 1

ferrous metals are metals that contain iron(not resistant to corrosion/oxidation)

Question 2

non-ferrous metals

Answer 2

copper | lead | tin | aluminum | zinc

Question 3

corrosion

Answer 3

when iron/steel react to water from air(salt water speeds up process)

Question 4

oxidation

Answer 4

when iron/steel reacts with air

Question 5

alloys

Answer 5

(resistant to corrosion) steel,copper,aluminium,nickel,magnesium

Question 6

stainless steel

Answer 6

an alloy made of iron + nickel + chromium

Question 7

3 ways to preserve metals

Answer 7

*painting
*galvanising
*electroplating

Question 8

process of painting metal

Answer 8

select latex anti-corrosive primer→remove all dirt/grease/grime→use wire brush to remove rust→sandpaper metal(rougher=more paint will stick)→double coat primer→sandpaper primer(clean off dust with sponge)→apply acrylic latex paint evenly

Question 9

tips for a better paint job

Answer 9

*use good quality paint brush
*spray paint metal
*use zinc chromate primer for rusted metal

Question 10

galvanising

Answer 10

applying protective layer of zinc to iron/steel to prevent rust(galvanised metal have a shiny silver grey surface)

Question 11

process of galvanising

Answer 11

immerse oil in liquid(remove impurities)→acid bath iron(to remove contaminants/chemical/rust)→dip iron in zinc ammonium chloride→bath iron in molten zinc(450°C)→remove excess zinc→cool metal

Question 12

electroplating

Answer 12

imposing one metal on top of different metal(passing elec current through salt solution of the metal)