C3.1 Theory Flashcards
Law of conservation of mass
In chemicals reactions, mass cannot be created nor destroyed
What happens to the mass of the product in a reaction with a closed system
the total mass will be the same at any point in time in any closed system.
What happens to the mass of the product in a reaction with a non closed system
Mass will be lost, not destroyed and is often lost as a gas
What is combustion
Combustion is a chemical process or a reaction between Fuel (Hydrocarbon) and Oxygen
Explain, in terms of particles, why the mass of substances increases after a combustion reaction
When a substance (eg copper) is heated up, the particles gain enough energy to react with the oxygen atoms in the air around it. These atoms then become part of the copper oxide molecules that from when copper reacts with oxygen. This increases the overall mass
What do balanced equations show
- how the atoms are rearranged in a reaction
- the relative amounts of each substance involved
State symbols
Liquid - (l)
Solid - (s)
Gas - (g)
Aqueous - (aq)
What are half equations
A half equations is a model for the change that happens to one reactant in a chemical reaction
What is an ionic reaction
A complete ionic equation shows the ions present in a reaction mixture
What are spectator ions
Ions that are present on both sides of the ionic equation, meaning that they have in part in the reaction
What is a net ionic equation
An equation where the spectator ions are cancelled out, leaving only the ions that are used in the equation behind
