Balancing Symbol Equations

1. Balance the following equation

Mg + HCl ________> MgCl2 + H2

NBs: When writing these out, the number 2 at the end of Cl and H is a small 2.

Mg is magnesium metal, found in group 2 of the periodic table.

HCl is hydrochloric acid

MgCl2 is magnesium chloride, an ionic compound (salt)

H2 is hydrogen - the test for hydrogen gas is when a test tube containing it is placed over a Bunsen burner it makes a squeaky pop.

On the LHS, there is 1 H and 1 Cl

On the RHS, there are 2 H`s and 2 Cl`s

To balance up, we put a big 2 in front of the HCl - note always use big front numbers to balance up equations

Answer should like this:

Mg + 2HCl -> MgCl2 + H2

2. Balance the following equation

NaOH + H2SO4 ____> Na2SO4 + H2O

NB: The number 2`s after H are small 2`s

NaOH is sodium hydroxide

H2SO4 is sulfuric acid

Na2SO4 is sodium sulfate

H2O is water

There is 1 Na on the LHS and 2 Na on the RHS - therefore put a big 2 infront of NaOH

We have:

2NaOH + H2SO4 -> Na2SO4 + H2O

There are 4 H`s on the LHS and 2 H`s one the RHS - therefore put a big 2 infront of the H2O

We have our answer:

2NaOH + H2SO4 -> Na2SO4 + 2H2O