Solving for grams (reaction problem)

 Chemistry Tutor: None Selected Time limit: 1 Day

Calcium hydride reacts with water to form calcium hydroxide and hydrogen gas.

(a) Write a balanced chemical equation for the reaction. (Use the lowest possible coefficients. Include states-of-matter under SATP conditions in your answer.)

(b) How many grams of calcium hydride are needed to form 6.491 g of hydrogen?

Jul 24th, 2015

a]CaH2(s)+2H2O=2H2 (g)+Ca(OH)2(s)

b]CaH2+2H and 2H2

40+2= 42 GRAM MES

H= 4 gram mes

42/  {6.491/4}

42/1.3

32 GRAMMES

Jul 24th, 2015

CaH2(s)+2H2O(l)=Ca(OH)2(s)+2H2(g)

6.4919/1.008= 3.22moles of hydrogen used.

For I mole of calcium hydride, 2 moles of hydrogen was formed hence the amount of calcium hydride used in moles is 3.22/2=1.61 moles of calcium hydride.

Hence mass= moles *molar mass which is 1.61moles*42.094= 67.77g

Hence 67.77g of calcium hydride was used.

This is the answer i got :/

Jul 24th, 2015

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Jul 24th, 2015
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Jul 24th, 2015
May 29th, 2017
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