Goiter / excessive growth of thyroid gland causes by the deficiency of:

Which element forms the maximum number of compounds with hydrogen?

Cooking vessels have wooden or bakelite handles because–

In a refrigerator; cooling is produced by–

If the edge of a cube is halved, then its volume reduces to _____times the actual volume.

Which of the following gas is not present in the atmosphere?

Which substance is added to make natural rubber hard and bouncy?

Which gas is used for unnatural ripening of fruits?