three molecules of oxygen react with four molecules of hydrogen to produce water molecules write a balanced chemical equation

ExpC

H

4

+  

2

O

2

→

C

O

2

+  

2

H

2

O

This is the balanced reaction equation for the combustion of methane.

Explanation:

The Law of Conservation of Mass basically states that matter can neither be created nor destroyed. As such, we must be able to show this in our chemical reaction equations.

If you look at the equation above, you'll see an arrow that separates the reaction equation into two parts. This represents the direction of the reaction.

To the left of the arrow, we have our reactants.

To the right of the arrow, we have our products.

The quantity of each individual element in the left must equal the quantity of each individual element in the right.

So if you look below, you'll see the unbalanced equation, and I'll try to explain how to balance the reaction.

C

H

4

+  

O

2

→

C

O

2

+  

H

2

O

Our reactants in this equation are  

C

H

4

and  

O

2

.

Our next step is to break these down into individual atoms.

We have:

1 C atom, 4 H atoms & 2 O atoms.

If you're confused by this, look to see the little number to the bottom right of each element, the subscript, and it tells you how many of each atom are in the molecule. Make sense?

Now we look to the other side of the equation.

Here we see our products are  

C

O

2

+  

H

2

O

Again, we break these down into individual atoms again.

We have:

1 C atom, 2 H atom, 3 O atom

- lead + phosphoric acid = hydrogen + lead(ii) phosphate