Question

balancing chemical equations worksheet

1. 2 h2 + 2 o2 -> 2 h2o
2. 2 mg + o2 -> mgo
3. li + f2 -> lif
4. k + o2 -> k2o
5. h2o2 -> h2o + o2
6. al + cl2 -> alcl3
7. ag2o -> ag + o2
8. h2 + n2 -> nh3

Explanation:

Step1: Balance the second equation

For \(Mg + O_2
ightarrow MgO\), first balance oxygen. There are 2 oxygen atoms in \(O_2\). So put 2 in front of \(MgO\) (\(Mg + O_2
ightarrow 2MgO\)). Then balance magnesium: put 2 in front of \(Mg\). The balanced equation is \(2Mg + O_2
ightarrow 2MgO\).

Step2: Balance the third equation

For \(Li+F_2
ightarrow LiF\), balance fluorine. There are 2 fluorine atoms in \(F_2\). Put 2 in front of \(LiF\) (\(Li + F_2
ightarrow 2LiF\)). Then balance lithium: put 2 in front of \(Li\). The balanced equation is \(2Li+F_2
ightarrow 2LiF\).

Step3: Balance the fourth equation

For \(K + O_2
ightarrow K_2O\), balance oxygen. There are 2 oxygen atoms in \(O_2\). Put 2 in front of \(K_2O\) (\(K+O_2
ightarrow 2K_2O\)). Then balance potassium: put 4 in front of \(K\). The balanced equation is \(4K + O_2
ightarrow 2K_2O\).

Step4: Balance the fifth equation

For \(H_2O_2
ightarrow H_2O+O_2\), balance oxygen. Let the coefficient of \(H_2O_2\) be 2 (\(2H_2O_2
ightarrow H_2O + O_2\)). Then balance hydrogen and oxygen: \(2H_2O_2
ightarrow 2H_2O+O_2\).

Step5: Balance the sixth equation

For \(Al + Cl_2
ightarrow AlCl_3\), balance chlorine. The least - common multiple of 2 and 3 (the number of chlorine atoms in \(Cl_2\) and \(AlCl_3\)) is 6. Put 3 in front of \(Cl_2\) and 2 in front of \(AlCl_3\) (\(Al+3Cl_2
ightarrow 2AlCl_3\)). Then balance aluminum: put 2 in front of \(Al\). The balanced equation is \(2Al + 3Cl_2
ightarrow 2AlCl_3\).

Step6: Balance the seventh equation

For \(Ag_2O
ightarrow Ag+O_2\), balance oxygen. Let the coefficient of \(Ag_2O\) be 2 (\(2Ag_2O
ightarrow Ag + O_2\)). Then balance silver and oxygen: \(2Ag_2O
ightarrow 4Ag+O_2\).

Step7: Balance the eighth equation

For \(H_2+N_2
ightarrow NH_3\), balance nitrogen. Put 2 in front of \(NH_3\) (\(H_2+N_2
ightarrow 2NH_3\)). Then balance hydrogen: put 3 in front of \(H_2\). The balanced equation is \(3H_2+N_2
ightarrow 2NH_3\).

Answer:

1. \(2Mg + O_2

ightarrow 2MgO\)

1. \(2Li+F_2

ightarrow 2LiF\)

1. \(4K + O_2

ightarrow 2K_2O\)

1. \(2H_2O_2

ightarrow 2H_2O+O_2\)

1. \(2Al + 3Cl_2

ightarrow 2AlCl_3\)

1. \(2Ag_2O

ightarrow 4Ag+O_2\)

1. \(3H_2+N_2

ightarrow 2NH_3\)