Calcium hydride reacts with water to form calcium hydroxide (aqueous) and hydrogen gas. How would you write a balanced chemical equation for the reaction? How many grams of calcium hydride are needed to form 4.600 of hydrogen?

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Answer 1 · 2016-06-11T16:06:14

#CaH_2(s) + 2H_2O(l) rarr Ca(OH)_2(aq) + H_2(g)uarr#

Approx. #100*g# calcium hydride are required.

If #4.6*g# of dihydrogen are evolved, this is a molar quantity of #(4.6*g)/(2.016*g*mol^-1)# #=# #2.28# #mol#.

If #2.28*mol# dihydrogen are evolved, then at least a an equivalent molar quantity of calcium hydride was used.

i.e. #2.28*molxx42.094*g*mol^-1" calcium hydride"# #=# #??g#