Question

Identify elements from A, B, C, and D and justify your answer.
A: On heating gives off gas and leaves some residue.
B: Burns in the air to form carbon dioxide and water.
C: Burns in the air to form carbon dioxide gas only.
D: Burns in the air to form water only.

Answer 1

Answer:

A -  calcium carbonate on heating gives colourless gas carbon dioxide and residue calcium oxide.

B - Methane burns with oxygen to form carbon dioxide and water.

C - When carbon burns completely excess of air (oxygen) it forms carbon dioxide. But if there is incomplete combustion, carbon monoxide is formed.

D - Hydrogen burns in air to form water

Answer 2

Answer:

yep he is correct the above one