Chemistry Paper 1
Conservation of mass
Quantitative Chemistry training before the targeted original question drill.
Adaptive teaching card
Make it concrete
Analogy
Conservation of mass is like changing a recipe: the particles, amounts and conditions decide what product you can make.
Why now: An analogy helps when the definition feels abstract.
Do this: Match each part of the analogy to the science idea.
Learn it
Mass is conserved in chemical reactions.
A balanced equation has the same number of each atom on both sides.
Apparent mass changes can happen when gases enter or leave a reaction vessel.