Balancing equations

What's here?

Lots of people think that balancing equations is really, really difficult.

But practice makes perfect, so click on the button on the left to get an equation to balance.
It's selected at random and you've got 60 seconds to get it right.

Click the button again for another equation ... and another ... and another!

Some hints

Remember:

• the number of each type of atom on the left must be the same as the number of each type of atom on the right;
• you can't change the formula of a substance just to get the equation to balance;
• treat groups of atoms such as SO₄ as a block; and
• look for atoms which have an even number on one side and an odd number on the other - multiply the substance with the odd number by 2 to make it even, then check again

Keep practising!