Chemistry S2 Flashcards
What so all chemical reactions produce
New Substances
Reactant +Reactant ➡️products
What is the sign for solid
s
What is the sign for liquid
l
Whats the sign for Gas
g
What does aqueous mean
(A substance desolved in water)
Whats the sign for Aqueous
aq
What is a exothermic reaction
An reaction where energy is given out .
What will happen to the temperature of the mixture in a exothermic reaction
The temperature of the reaction mixture will increase!
What is a endothermic reaction
Energy taken in
What will happen to the temperature of the substance during an endothermic reaction?
The temperature of the reaction mixture will descrese
What is electrolysis
It is when electricity can be used to separate compounds into the elements they contain
What is a fuel
A fuel is a chemical which burned to release energy
What is combustion
Term used to describe the burning of a fuel in the presence of oxygen
What happens when a fuel burns
It reacts with oxygen in the air
How much oxygen is in the air
21% oxygen,78% nitrogen and 1% other gases
What is the test for oxygen
Relights a glowing splint !
Combustion of carbon
Carbon reacts with oxygen in the air to form carbon dioxide
Carbon(s) + Oxygen(g) → Carbon dioxide(g)
Test for carbon dioxide
Carbon dioxide gas turns limewater milky
What are the 2 types of combustion
Complete combustion and Incomplete combustion
What is there is a lot oxygen in the air to burn carbon what will this produce and what kind of combustion is it
It will produce Carbon dioxide(g) and will be complete combustion
What does incomplete combustion make
Carbon Monoxide
What does complete combustion make?
Carbon dioxide
What is a carbon monoxide
Colourless odourless toxic gas
Combustion of hydrogen equation
Hydrogen(g)+Oxygen(g)➡️water(l)
Test for hydrogen
Hydrogen gas burns with a squeaky pop
What are fossil fuels
Coal,Oil and natural gases are all fossil fuels
When where fossil fuels formed
Millions of years ago from the remains of living things
When did the formation of coal start
350million years ago
Where did coal start to form
Where there was extensive plant growth in places like flooded forests and swamps
Coal formation what happened
When fern like trees died they fell into swamps and could not decay completely so they turned into a layer of peat then layers of mud and earth covered the peat and burying and compressing it
Coal formation what happened after the peat was covered
As the layers built us and compressed it even further the pressure increased so did the temperature which eventually tured the peat into coal
What does finite mean
Limited
Combustion of fossil fuels how do fossil fuels undergo combustion
With oxygen in the air
The products of combustion are?
Carbon dioxide and water
What is a HYDROCARBON
Molecules that consist of carbon and hydrogem ONLY
What is crude oil
Contains a mixture of hyrdrocarbons
(1)Oil and gas formation when did it happen and where
Oil and natural gas were formed more than 100 million years ago in seas or lakes that had a lot of plankton
(2)Oil and gas formation what happened next
The plankton died and sank to the bottom of the sea
(3) oil and gas formation? what happened after the plankton sunk
The dead plankton covered with layers of sand and mud at the bottom
(4) oil and gas formation what happened after they where covered
As the layers built up the high temperature and pressure formed oil and natural gas
(5) oil and gas formation what happened after the high pressure and high temperature
Once the oil and natural gas had formed they started to migrate upward and became trapped in layers of impermeable rock
(6)oil and gas formation what happened after the oil and gas came up
The oil and gas accumulated to form oil fields and gas fields
