Question #dc69a

1 Answer
Apr 22, 2016

9.45g

Explanation:

ok so first find the moles of iron in 19.69g
use the formula mol=(mass)/(ar) ar is the atomic relative mass.
mol=19.69/56
mol=0.3516approx0.35
now from the equation we know that 2 moles of aluminium make 2 moles of iron.now use the ratio method to get the moles of aluminium in 0.35mols.so it will be 0.35mols as they both have the same ratio.
so now use these moles to find the mass of aluminium
mol=(mass)/(ar)
0.35*27=mass
9.45g