Chemistry
The ore that can be concentrated by using magnetic separation:
- Corundum
- Haematite
- Calamine
- Bauxite
Answer
Haematite
Reason — Magnetic separation works when either the ore or the gangue shows magnetic behaviour. Haematite, an iron ore, is weakly magnetic, whereas its common impurity (silica) is non-magnetic. When the crushed mixture is passed over a high-intensity magnetic separator, the haematite particles are attracted and collected separately from the non-magnetic gangue, concentrating the ore.
Related Questions
In the reaction given below sulphuric acid acts as a/an:
S + 2H2SO4 ⟶ 3SO2 + 2H2O
- Non-volatile acid
- Dibasic acid
- Oxidising agent
- Reducing agent
Assertion (A): The tendency of losing electrons increases down the Group.
Reason (R): The most reactive metal is placed at the top of Group 1.
- Both (A) and (R) are true, and (R) is the correct explanation of (A).
- Both (A) and (R) are true, and (R) is not the correct explanation of (A).
- (A) is true but (R) is false.
- (A) is false but (R) is true.
The diagram given below shows the bonding in the covalent molecule AB2.

Which option represents the correct electronic configuration of atoms A and B before combining together to form the above molecule?
A B 1 2, 4 2, 8, 6 2 2, 4 2, 8, 7 3 2, 8 2, 8, 8 4 2, 6 2, 8, 7 Which of the following options has all the compounds which are members of the same homologous series?
- CH4, C2H6, C3H8
- CH4, C2H6, C3H6
- C3H4, C3H6, C3H8
- C2H4, C3H6, C4H10