yr10 chemistry- chemical reactions, speed of reactions

combustion fuel

fuel + oxygen → carbon dioxide +water

combustion metal

metal +oxygen → metal oxide

acid - base

acid + base → salt + water

acid - metal

acid + metal →salt + hydrogen

acid - carbonate

acid + carbonate →salt + water + carbon dioxide

Decomposition

A → B + C
eg water → hydrogen + oxygen

Synthesis

B + C → A

Displacement

A + BC → B + AC

Precipitation

AB + CD → AD +CB

Law of Conservation of Mass

Matter is not created nor destroyed

Law of Constant Proportion

ratio of each atom in a compound is always the same, no matter how they're formed.

Evidence of a chemical reaction

- colour change
- disappear / appear product
- odur change
- temperature change
- formation of gas/ bubbles
- formation of precipitation

rate of reaction

measure of how fast a chemical reaction occurs

increasing concentration

increasing amount of reactant
more reactant particles present → increase frequency of collisions →reactants turn into products faster

Increase in temperature

increase in heat energy→ increasing in kinetic energy→ particles move faster →particles collide more frequently →reactants turn into products faster

increase surface area

more surface area of a reactant in contact with other reactants→ increase frequency of collisions → reactants turn into products faster

catalyst

- speeds the chemical reaction but isn't part of it
- speeds up the chemical reaction by bringing reactants in contact with each other at the correct orientation
- reduces energy required by the reactants to turn into products and the reaction occurs faster.