Chemical Changes Flashcards
What is a chemical reaction
A chemical reaction involves atoms of starting reactants to make new products. The reactants are used up.
What is a physical reaction
Involves change of state or temporary change to the substance
3 signs of a reaction occurring
1: effervesced
2: colour change
3: change of state
Chemical reaction definition
A change in which atoms are rearranged to create new substances
combustion
A chemical reaction on which a substance reacts quickly with oxygen and gives out heat
conservation of mass
In a chemical reaction, the total mass of reactants is equivalent to total mass of products. Mass is conserved in chemical reactions and in physical changes
Decomposition
A chemical reaction in which a compound breaks down to form simpler compounds and/or elements
displacement
when a metal takes the place of another less reactive metal in a compounds
endothermic reaction
Takes energy from its surrondings
Exothermic reaction
releases energy into its surroundings
neutralisation
When an acid and a base react together to make a new pH and mixture
physical change
A change that is reversible, in which new substances are not made
product
A substance that is made in a chemical reaction
reactant
A starting substance in a chemical reaction
Thermal decomposition
When a compound is broken down using heat alone
