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chem quesiton (1 Viewer)

simDS

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the balanced equation is 2Al + 3H2SO4 --> Al2(SO4)3 + 3H2

how much Aluminum Sulfate can be produced from 10g of aluminum (unlimited H2SO4)?

how much aluminum sulfate can be produced from 10g of aluminum when only 0.3 mol H2SO4 is present?

thanksss
 

js992

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Calculate how many moles 10g of aluminium is.

Since 2 moles of aluminium produces 1 mole of aluminium sulfate, whatever you get for moles of aluminium, divide by 2.

Once you have moles of aluminium sulfate, convert back to mass in grams
 

richman92

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not so hard...

case 1,
moles of Al = 10/27 = 0.37 moles

2Al + 3H2SO4 --> Al2(SO4)3 + 3H2
0.37 3/2*0.37 1/2*0.37 3/2*0.37 moles
0.37 0.55 0.185 0.55 moles

mass of Al2(SO4)3 = 0.185 * (27*2+ (32+16*4)*3) = 0.185 * 342 = ...g

case 2, if 0.37 moles of Al react, we need 0.55 moles of acid, but only 0.3 mol of acid is present hence acid is used up and Al is excess.

2Al + 3H2SO4 --> Al2(SO4)3 + 3H2
2/3*0.3 0.3 1/3*0.3 0.3
0.2 0.3 0.1 0.3 moles

mass of Al2(SO4)3 = 0.1 * 342 = 34.2 g
 

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