M apa = 1*2 + 16 = 18 g/mol
nr moli = masa / M apa => masa = nr moli * M apa = 18 * 2 = 36 g
36 g........................ a g.......... v L
2H2O + 2Na ---> 2NaOH + H2
2*18 .......................... 2*40......22,4
=> a = 2*40*36/2*18 = 80 g NaOH (partea solida)
v = 22,4*36/2*18 = 22,4 L H2