Chemistry Chemical Reactions Flashcards
What is the law of conservation of mass?
Mass is not created nor destroyed by chemical reactions
What are the signs that a chemical reaction has occured?
Changes in colour
Solid appears or disappears
A gas is formed
Sudden changes in temperature
Light appears
The things we have at the start of a chemical reaction are called what?
Reactants
The things we have at the end of a chemical reaction are called what?
Products
What is a reaction which gives off heat called?
Exothermic
What is a reaction which takes in heat called?
Endothermic
What things can affect the rate of reaction?
Surface area
Concentration
Temperature
Presence of a catalyst
Why does temperature affect the rate of reaction?
At warmer temperatures, the particles are vibrating more, so they are more likely to come in contact with other particles and react with it.
Why does surface affect the rate of reaction?
Surface area affects the rate of reaction as there is more surface where a substance can react with another substance.
