Question

1.Magnesium ribbon is rubbed before burning because it has a coating of

(a)basicmagnesiumcarbonate

(b)basicmagnesiumoxide

(c)basicmagnesiumsulphide

(d)basicmagnesiumchloride​

Answer 1

Answer:

(b)basicmagnesiumoxide

Explanation:

Magnesium is a highly reactive metal. When exposed to air it forms a layer of magnesium oxide on its surface, which prevents further reaction of magnesium with oxygen. Magnesium ribbon is rubbed before burning because it has a coating of basic magnesium oxide.

Answer 2

Answer:

ans is option (B)

Explanation:

WHEN MAGNESIUM IS  LEFT IN AIR IT HAS A COAT OF OXYGEN OVER IT WHICH PREVENTS IT FROM BURNING i.e it is being rubbed with a sand paper to remove it MgO coating