Balance a Chemical Reaction

Classes 7–10 · about 6 minutes · free, no sign-up

What you will learn

Balance chemical equations by changing the number of molecules, and explain that atoms are rearranged, never created or destroyed, so mass is conserved.

How to play

Pick a reaction, such as making water or burning gas.
Use plus and minus to add molecules to each side.
Watch the atom table: every kind of atom must match before and after.
Finish three challenges, then try rusting and photosynthesis.

Go deeper

Notes, practice questions and tests for the same topic:

Class 10 Science: Chemical Reactions and Equations NCERT chapters → Class 9 Science: Atoms and Molecules NCERT chapters →

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