How many of the following will evolve H2 gas when dissolved in water under room conditions ? B2H6, SiH4, CH4, Al, B, Na, PCl3, P(white), Fe. Initially it seemed easy to me and I got 7(all except PCl3,CH4) .Correct me if I am wrong here. Well the answer given was 3.(Which given were B2H6,SiH4...The other one I hope is Na).

What did I do wrong here?Does the temperature condition hold that much difference here?How do you predict products like these?