Question

What happens when : (a) A piece of calcium is dropped in water
When, Calcium Reacts With Water,


The Following reaction Takes Place :


Ca + 2H₂O ----------> Ca(OH)₂ + H₂


Means, Calcium When added in Water, Gives Calcium Hydroxide or Slaked Lime and Hydrogen Gas.


Slaked Lime is White in Color and, The Mug/Beaker Becomes Hot as This is an Exothermic Reaction.


And One more question arises here,


Q. How are we 100\%100% sure that, the gas released is H₂ Gas?

A. We can be sure by bringing a lighted matchstick near the mouth of test tube. The gas on coming in contact with the flames, It burns with a pop sound. Hence, We can be 100\%100% that gas is H₂​

Answer 1

Answer:

there are 2hydrogen in water. so we are sure that it is h2 gas