Chemical effects of electric current

Alloys of metals

• allow electric current to flow through them

• do not allow electric current to flow through them

• sometimes allow and sometimes do not allow electric current to flow through them

• None of these

Choose insulator from the following:

• Distilled water

• Plastic

• Wood

• All of them

Tin cans used for storing food are made by electroplating

• copper on iron

• iron on tin

• tin on zinc

• tin on iron

Iron is coated with (a)   to protect it from corrosion.

The article to be electroplated is made

• the anode

• the cathode

• either anode or cathode

• none of these

The filament of the bulb gets heated to a high temperature due to the

• magnetic effect of current

• heating effect of current

• chemical effect of current

• all of these

During electrolysis of water,

• hydrogen gas is produced

• oxygen gas is produced

• water is produced

• both (a) and (b)

An electric current can produce

• heating effect

• chemical effect

• magnetic effect

• all of the above

Which of the following does not conduct electricity?

• Sugar solution

•  Vinegar solution

• Lemon juice solution

• Caustic soda solution

Why do we add little dilute sulphuric acid to copper sulphate solution during electroplating?

• To increase acidity

•  To increase conductivity

• So that the colour becomes more prominent

•  To burn copper sulphate