(Now EoY revision 22/5/25)Chemistry LGS 3/4/25 Flashcards
(20 cards)
Exothermic
A reaction that gives OUT energy to surroundings
Endothermic
A reaction that takes IN energy from it’s surroundings
Fuel
A substance that releases energy when burnt
Non renewable energy
energy that comes from a source that will run out in a lifetime
Renewable Energy
energy that comes from a source that can naturally replenish
Sustainable energy
energy that comes from a source that doesn’t get depleted
Fossil Fuels
Non renewable resources; coal/gas/oil burnt to give off energy
Biofuels
Renewable fuels; ethanol/biodiesel burnt off to give off energy
Displacement reactions
When a more reactive metal takes place of a less reactive metal - exothermic and gives off energy
Electrochemical cell
A device that generates energy from chemical reactions
The words for changing between the states of matter
melting,
freezing,
evaporation, condensation,
sublimation -solid to gas
deposition -gas to solid
What is diffusion?
Particles moving from high concentration area to low concentration area
What makes diffusion faster?
A bigger difference of concentration between the high and low concentration/increase surface area
definitions for elements, compounds and mixtures
Element- a substance made up of one type of atom
Compounds- a substance that has more than one type of atoms that are chemically bonded
Mixtures- a substance that has 2 or more atoms in any ratio
3 properties of metals
Shiny
Malleable
Conduct electricity/heat
3 properties of non-metals
Dull
Brittle
poor conductor of heat
names of groups 1, 7 and 8
1- Alkali Metals
2- Halogens
3- Noble gases
How do metals from group one react with water?
Hydrogen gas is given off and the metal hydroxide is produced
What is displacement?
When a more reactive metal takes place of a less reactive metal in a reaction
What is thermal decomposition?
Where a compound is broken down into simpler compounds or elements when heated
