The metal that gives hydrogen gas upon treatment with both acid as well as base is :

The correct statements among (a) to (d) are :
(a) saline hydrides produce H₂ gas when reacted with H₂O.
(b) reaction of LiAlH₄ with BF₃ leads to B₂H₆.
(c) PH₃ and CH₄ are electron - rich and electron - precise hydrides, respectively.
(d) HF and CH₄ are called as molecular

The synonym for water gas when used in the production of methanol is :

The number of water molecule(s) not coordinated to copper ion directly in CuSO₄.5H₂O, is :