Question

Calcium reacts with element y and release gas z indentify them

Answer 1

when calcium oxide react with oxygen the new product of calcium oxide is format
Ca + O = CaO
so,
y is calcium
z is calcium oxide

Answer 2

Hey...

Calcium reacts with water form calcium hydroxide and librates hydrogen gas..

Ca(s)+2H2O(l)------->Ca(OH)2(aq)+H2(g)......

So ,in this Question y = H2O (water) ,and z = H2 (Hydrogen gas)


Hope this will help you...