English National Curriculum - Science
Mission Objectives
State the law of conservation of mass: total mass of reactants equals total mass of products
Describe how to balance equations using multipliers and subscripts
Explain apparent mass changes in open reactions due to gases entering or leaving
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Words and meanings to learn
conservation of mass
the total mass of the products in a chemical reaction is equal to the total mass of the reactants because no atoms are created or destroyed
balanced equation
a symbol equation in which the number of atoms of each element is the same on both sides of the equation
reactant
a substance that takes part in a chemical reaction and is present at the start
product
a substance formed in a chemical reaction, present at the end of the reaction
state symbol
a letter in brackets used in a symbol equation to show the physical state of a substance: (s) solid, (l) liquid, (g) gas or (aq) aqueous (dissolved in water)
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