Balancing Reaction
1.0 Balancing chemical equations
1.0 Balancing chemical equations
A chemical reaction is a process by which one set of chemicals is transformed into a new set of chemicals.
A chemical equation uses standard chemical symbols to describe the changes occurring during a reaction.
$${\text{Reactants}} \to {\text{Products}}$$
Example: $${H_2} + {O_2} \to {H_2}O$$
Hydrogen and oxygen combine to form water. But the equation is not balanced.
There are 2 oxygen atoms on the reactant side of the equation, but only one on the product side.
If we place a 2 in front of the water on the product side, we will balance the oxygen.
$${H_2} + {O_2} \to 2{H_2}O$$
We now need to balance the hydrogen. Place a 2 before the hydrogen on the reactant side of the equation.
$$2{H_2} + {O_2} \to 2{H_2}O$$
So, we have balanced the above equation.
The stoichiometric coefficients multiplying the chemical formulas tell you the relative number of moles of each substance that reacts or is produced in a chemical reaction.
Therefore, we can understand from the balanced equation that 2 moles of hydrogen and one mole of oxygen combine 2 form 2 moles of water.
A chemical equation may also tell you what physical state the reactants and products are in. The state and symbol are used as following,
- s (solid)
- l (liquid)
- g (gas)
- aq (aqueous solution)
These are found as subscripts after each reactant and product.
