corrosion

Question 1

what is corrosion

Answer 1

when metals react with water and/or oxygen to create oxides and hydroxides. In corrosion electrons transfer from one reactant to another.

Question 2

What are the three main types of corrosion

Answer 2

rusting, tarnish and verdigris.

Question 3

What is rusting

Answer 3

when iron or steel react with oxygen and water to form iron oxide or rust. It is a complicated reaction and turns an orangy colour.

Question 4

What speeds up rusting

Answer 4

salt and water

Question 5

tarnish

Answer 5

when silver reacts with hydrogen sulfide to form a black coating of silver sulfide or tarnish.

Question 6

vedigris

Answer 6

when copper reacts with gases in the air to form copper hydroxide and copper carbonate. this creates a green coating of verdigris on the metal-which is a mixture between to two copper compounds.

Question 7

Why do some metals corrode quicker than others

Answer 7

Some metals are very reactive and react very quickly with the air, this create a strong tight layer over the metal and stops it from corroding.

Question 8

what is the chemical equation for rusting

Answer 8

iron+oxygenated gas+water=hydrated iron (iii) oxide

Question 9

what is the chemical equation for tarnish

Answer 9

silver+hydrogen sulfide=silver sulfide+hydrogen gas

Question 10

what is the chemical equation for veredris

Answer 10

copper+water+carbon dioxide+oxygen gas=copper carbonate+copper hydroxide