Question

what happens when calcium reacts with water?

Answer 1

Answer:  A white suspension of calcium hydroxide is formed, and hydrogen gas is given off. 

Calcium oxide is not the product, since it would react violently with water itself. 

Ca + 2H2O ----> Ca(OH)2 + H2

Answer 2

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 $100\%$ 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 $100\%$ that gas is H₂

Thanks!!