4Al(s) + 3O2(g)2Al2O3(s)

Question

Delta H reaction = -3351.4 kJ

How much energy is transferred when 42.6 g of aluminum reacts to form aluminum oxide?

Thanks

Answer 1

well, four moles of Al yields 3351J

figure the moles of Al in 42.6g

moles= 42.6/atomicmassAl

molesgiven/4=Heat/3351.4kJ
solve for Heat.

Answer 2

When calculating the moles of Al in 42.6 g, do you multiply the molar mass by four or just Mr of one Al atom?
Thanks

Answer 3

moles= 42.6g/26.9

(42.6/26.9)/4=heat/3351J