Iron Oxide reacts with aluminium to form iron and aluminium trioxide.
Write the chemical equation to show the reaction and balance it.

Explanation

Reaction is Iron Oxide reacts with aluminium to form iron and aluminium trioxide.
Step : 1
i) Write the equation with the correct chemical formulae for each reactant and product.
Eg : The skeleton equation is `Fe_(2)O_(3) +Al rarr Fe +Al_(2)O_(3)`
Step : 2
i) Compare number of atorms of each element on both sides.
ii) We must put suitable numbers as the coefficients before the formula to balance the total number of atoms on both sides of an arrow mark.
iii)In this case `Fe_(2)O_(3)`, the most complex substance. Better to start with it.
Look at the Iron (Fe)
By observing there are 2 iron atoms on the left side, but only one atom on the right side.
ii) If we add 2 to Fe on the right, then the equation is `Fe_(2)O_(3)+Al rarr 2Fe+Al_(2)O_(3)`
Look at the oxygen (O)
i) By observing there are 3 oxygen atoms on the left side, 3 atoms on the right side.
ii) Both are equal. So, no need to add coefficients here.
Hence the equation is `Fe_(2)O_(3)+Al rarr 2Fe+Al_(2)O_(3)`
Look at the aluminium (AI)
i) By observing there is 1 aluminium atom on the left side, but two atoms on the right side.
ii) If we add 2 to Al at left side, then the equation is `Fe_(2)O_(3)+2Al rarr 2Fe+Al_(2)O_(3).`
iii)Therefore, the equation is balanced.
Step : 3
i) Check whether all the coefficients of the substances has a common factor.
ii) If so, divide those by common factor to obtain lowest ratio of the substances.
Eg : In the above balanced equation `Fe_(2)O_(3)+2Al rarr 2Fe+Al_(2)O_(3),` no common factor of the coefficients.
iii)Hence no need to divide.
Step : 4 )
Verify the equation for the balancing of atoms number and kind wise on both sides of the equation.
Eg : In the above equation number of iron (Fe) atoms in left side is 2 and right side is 2.
Number of oxygen atoms in left side is 3 and right side is 3.
Number of aluminium atoms in left side is 2 and right side is 2.
ii) Both sides are equal.
iii)Hence the equation is balanced.
Hence the given table can be changed like this