Scientists use a special way of writing to describe what happens in a chemical reaction. They describe a chemical reaction by writing a chemical equation using chemical symbols to represent the atoms taking part. Below is an example of a chemical equation using chemical formulae instead of words..
tells us that two molecules of hydrogen gas react with one molecule
of oxygen gas to produce two molecules of water. The equation has two
sides. On the left of the arrow we put the reactants(the chemicals that
react together). On the right side of the arrow we put the products
(the chemicals) that are formed or produced.
We can see that two molecules of hydrogen react with one molecule of oxygen to produce two molecules of water
Why do we have
a 2 in front of the water and the hydrogen molecule in the equation?
This is called "BALANCING the equation".
What this means
is that we have to have the same number of each atom on each side of
the arrow in the equation.
Methane and oxygen react to form carbon dioxide and water
CH4 + 2O2 => CO2 + 2H2O
The equation reveals that molecule/s of methane react/s with molecule/s of oxygen to form molecule/s of carbon dioxide and molecule/s of water.
How many oxygen atoms on the right of the equation
How many oxygen atoms on the left of the equation
How many hydrogen atoms on the right of the equation
How many hydrogen atoms on the left of the equation
How many carbon atoms on the right of the equation
How many carbon atoms on the leftt of the equation
Write an equation for each of the reactions on the next page.
|Go to the reactions