Chemistry MCQ

Assertion (A): Froth floatation process is employed for the concentration of sulphide Ores.
Reason (R): Sulphide ores are heavy weight ores.

Assertion (A): Highly reactive metals can be used as reducing agent.
Reason (R): Highly reactive metals can displace metals of lower reactivity from their compounds.

Assertion (A): Carbon can easily reduce the oxides of highly reactive metals.
Reason (R): Highly reactive metals have more affinity for oxygen than carbon.

The principal metal in an alloy known as type metal Is :

The conversion of the concentrated ore into oxide takes place through the calcination and roasting processes.
Which of the following pairs of involved process and the concerning ore are correct?
P. Calcination: Metallic carbonates; Roasting: Hydrated metallic oxides
Q. Calcination: Metallic carbonates, Roasting: Metallic sulphides
R. Calcination: Metallic sulphides; Roasting: Metallic carbonates

The ore which cannot be concentrated by froth floatation process is :

A substance added to an ore to get rid of earthly impurities, during the formation of a fusible compound is called

Duralumin is an alloy of :

Aluminium powder is used in thermite welding because :

During electrolytic reduction of alumina, the electrolyte is covered with coke powder :

During electrolytic reduction of alumina the electrolyte consists of :

The compounds of metals found in nature and associated with earthly impurities are called :

An oxide of iron is :

Metallic chlorides in general conduct electricity in :

Elements in molten state, on mixing and the cooling form a homogeneous called alloy are :