Balancing Equations: Practice

​ Mg + O2 ---> MgO

​First: Determine the number of atoms for each element.

​

Mg

O

​

Left side is for the Reactants Right side is for the Products!

​ Mg + O2 ---> MgO

​Second: Pick an element that is not equal on both sides of the equation.

​

1 Mg 1

2 O 1

​

How many atoms does Mg have on both sides? How many atoms does O have on both sides?

​ Mg + O2 ---> MgO

​Third: Add a coefficient in front of the formula with that element.​ Multiply the subscripts by the coefficients, and adjust your counts!

Mg + O2 --->​ 2MgO

1 Mg 2

2 O 2​

​

How many atoms does Mg have on both sides? How many atoms does O have on both sides?

​ Mg + O2 ---> MgO

​Fourth: Continue adding coefficients to get the same number of atoms of each element on each side. ​

2Mg + O2 --->​ 2MgO

2 Mg 2

2 O 2​

​

Are the elements equal on both sides? If yes, we're done!

2Mg2

2O2​

This is our final product!

Ca + O2 ---> CaO

What's our first step?

Ca

O​

Check your notes!

Ca + O2 ---> CaO

What's our second step?

1 Ca 1

2 O​ 1

Check your notes!

Ca + O2 ---> 2CaO

What's our third step?

1 Ca 2

2 O​ 2

Check your notes!

2Ca + O2 ---> 2CaO

What's our fourth step?

2 Ca 2

2 O​ 2

Check your notes!

2 Ca 2

2 O ​2

This is our final product!