Transition Elements

Question 1

What colour are copper compounds normally?

Answer 1

Blue

Question 2

What colour are iron (II) compounds normally?

Answer 2

Pale green

Question 3

What colour are iron (III) compounds normally?

Answer 3

Orange/Brown

Question 4

What are transition elements normally used as?

Answer 4

Catalysts, eg. iron in the Haber process or nickel in the manufacture of margarine.

Question 5

What happens to a transition metal carbonate if it is heated?

Answer 5

It will thermally decompose to give the metal oxide and carbon dioxide.

Question 6

What happens in a precipitation reaction?

Answer 6

Sodium hydroxide solution reacts with compounds of each transition metal to form a solid (metal hydroxide precipitates) of a particular colour. This identifies the presence of a transition metal ion.

Question 7

What are the colours of the precipitate for Cu^2+ ions, Fe^2+ ions and Fe^3+ ions?

Answer 7

Cu^2+ ions - blue
Fe^2+ ions - grey/green
Fe^3+ ions - orange/brown gelatinous