Reactions Revistion Flashcards
(18 cards)
What is a balanced symbol equation?
Chemical formulae represent reactants and products and it shows how atoms are rearranged. Eg NaOH + HCl = NaCl + H2O
What is a chemical reaction?
A change in atoms where they are rearranged to create new substances
What is combustion?
When a reaction occurs quickly with oxygen to give out light and heat
What is conservation of mass?
The total mass of reactants is equal to the mass of products
What is decomposition?
When a compound breaks down to form simpler compounds or elements
What is a discreet number?
It only has whole number values
What’s an endothermic change?
It takes in energy from the surroundings
What is an exothermic change?
It transfers energy to the surroundings
What is a fossil fuel?
A fuel made from animals and plants that died millions of years ago, e.g. oil
Define fuel
And material that burns to transfer energy
What is a hazard?
A source of danger
Define non-renewable fuel?
They form out millions of years and when they will run out
What is oxidation?
Reaction when substances react with oxygen to form oxides
Define physical change
A reversible change like a change of state
Define a product
The substance made by chemical reaction
Define reactant
The starting substance of a chemical reaction
What is risk?
The chance that hazard will cause injury
Defined a word equation
Representation of a chemical formula using words and an arrow, reactants are on the left and products are on the right
