C1
Changes of state:
➢ Reversible
➢ Mass is conserved
➢ Physical processes
➢ When particles gain or lose energy, through heating or cooling, they change state
➢ Amount of energy required for substances to change depends on whether the force
between the particles are strong and weak
Earth’s early atmosphere:
➢ Earth was formed 4.6 billion years ago
➢ Highly active volcanoes existed; their constant eruption released a lot of carbon dioxide
➢ Volcanic activity released nitrogen which slowly built up in the atmosphere, water
vapour condensed to form the oceans. Formation of oceans removed carbon dioxide
➢ Photosynthesis increased oxygen concentration through algae for complex life forms
such as animals to evolve
➢ Marine animals evolved
➢ Carbon dioxide, oxygen, nitrogen, water vapour, methane and ammonia were produced
Common atmospheric pollutants from fossil fuels:
➢ Burning fossil fuels produces carbon dioxide, carbon monoxide and other pollutants
➢ Cars produce nitrogen oxide
➢ Incomplete combustion happens when fuels are burned in insufficient oxygen
➢ Sulfur is an impurity that is present in fossil fuels
Consequences of atmospheric pollutants:
➢ Particulates cause respiratory problems
➢ Sulfuric acid is a major part of acid rain. This can cause corrosion, weathering and sine
organisms to die
➢ Nitric acid can cause acid rain and create the same problems as sulfuric acid
➢ Carbon monoxide binds to haemoglobin restricting the transportation of oxygen
Reducing emissions from power stations:
➢ Wet scrubbing
➢ Electrostatic precipitator
Reducing pollutants from motor vehicles:
➢ Using catalytic converters, converts nitrogen monoxide to harmless nitrogen and oxygen
➢ Using low sulfur fuels
➢ Using more efficient engines
➢ Taking public transport
➢ Setting legal limits on exhaust emissions
Testing for hydrogen:
, ➢ Hold a lit splint at the open end of a test tube containing a gas
➢ If the gas is hydrogen a squeaky pop sound will be produced
➢ Noise is generated because hydrogen burns rapidly in the presence of oxygen
Testing for oxygen:
➢ Insert a glowing splint into a test tube containing a gas
➢ If the gas is oxygen the splint will relight
Testing for carbon dioxide:
➢ Bubble through or shake carbon dioxide with lime water
➢ The solution will turn from clear to cloudy
Oxidation and reduction:
➢ OIL RIG
➢ Oxidation is loss
➢ Reduction is gain
Energy transfer:
➢ Energy is transferred in reactions, not created or destroyed
➢ Endothermic reactions- energy from the surroundings is transferred to the reacting
chemicals causing the temperature of the surroundings to decrease
➢ Exothermic reactions- energy from the reacting chemicals is transferred to the
surroundings, increasing the temperature
Requirements for a reaction to happen:
➢ Collisions- reacting particles must collide
➢ Activation energy- collisions must take place with sufficient energy for a reaction to
occur
Reaction profiles: exothermic to endothermic
Catalysts:
➢ Can increase reaction rates by increasing the likelihood of successful collisions. They
achieve this by lowering the activation energy
Chemical bonds:
➢ Measures the strength of chemical bonds
➢ Total bond energy of the product - total bond energy of the reactants
, ➢ Measured in KJ.mol
➢ Bond making is exothermic
➢ Bond breaking is endothermic
Chemical cell:
➢ Batteries & cells contain chemicals that react to produce electricity
➢ Can be produced by connecting 2 different electrodes and putting them in a liquid
electrolyte
Fuel cells:
➢ Produces electrical energy
➢ Uses a reaction between hydrogen and oxygen. Fuel is added to the cell and then there’s
a constant supply of oxygen. This fuel is oxidised and creates a voltage
➢ Advantages of this are it’s compact and lightweight, reliable, less pollution and highly
efficient
➢ Disadvantages are it has to be stored at high pressure and is explosive
➢ Anode- hydrogen molecules= hydrogen ions + electrons
➢ Cathode- hydrogen ions + oxygen molecules= water
Greenhouse effect:
➢ Greenhouse gases keep the earth warm. Can cause global warming if it becomes too
strong
➢ Sun emits radiation that enters the atmosphere towards the earth. Earth absorbs some of
the radiation and reflects the rest back into the atmosphere. Greenhouses gases absorb
this radiation and re-radiate the energy in all directions increasing the earth’s
temperature
Human activity and greenhouse gases:
➢ Landfill- sites are increasing. More waste is decomposing and decomposition releases
methane
➢ Agriculture- animals release methane during digestion
➢ Deforestation- less trees means less photosynthesis which means less carbon dioxide is
being removed from the atmosphere
➢ Burning fossil fuels- releases carbon dioxide
Global climate change:
➢ Melting polar ice caps- causes sea levels to rise which cause flooding and erosion of
coastal regions
➢ Natural events- severity of extreme events such as storms, heatwaves and droughts
➢ Water availability- changes in water availability could affect species distribution
Changes of state:
➢ Reversible
➢ Mass is conserved
➢ Physical processes
➢ When particles gain or lose energy, through heating or cooling, they change state
➢ Amount of energy required for substances to change depends on whether the force
between the particles are strong and weak
Earth’s early atmosphere:
➢ Earth was formed 4.6 billion years ago
➢ Highly active volcanoes existed; their constant eruption released a lot of carbon dioxide
➢ Volcanic activity released nitrogen which slowly built up in the atmosphere, water
vapour condensed to form the oceans. Formation of oceans removed carbon dioxide
➢ Photosynthesis increased oxygen concentration through algae for complex life forms
such as animals to evolve
➢ Marine animals evolved
➢ Carbon dioxide, oxygen, nitrogen, water vapour, methane and ammonia were produced
Common atmospheric pollutants from fossil fuels:
➢ Burning fossil fuels produces carbon dioxide, carbon monoxide and other pollutants
➢ Cars produce nitrogen oxide
➢ Incomplete combustion happens when fuels are burned in insufficient oxygen
➢ Sulfur is an impurity that is present in fossil fuels
Consequences of atmospheric pollutants:
➢ Particulates cause respiratory problems
➢ Sulfuric acid is a major part of acid rain. This can cause corrosion, weathering and sine
organisms to die
➢ Nitric acid can cause acid rain and create the same problems as sulfuric acid
➢ Carbon monoxide binds to haemoglobin restricting the transportation of oxygen
Reducing emissions from power stations:
➢ Wet scrubbing
➢ Electrostatic precipitator
Reducing pollutants from motor vehicles:
➢ Using catalytic converters, converts nitrogen monoxide to harmless nitrogen and oxygen
➢ Using low sulfur fuels
➢ Using more efficient engines
➢ Taking public transport
➢ Setting legal limits on exhaust emissions
Testing for hydrogen:
, ➢ Hold a lit splint at the open end of a test tube containing a gas
➢ If the gas is hydrogen a squeaky pop sound will be produced
➢ Noise is generated because hydrogen burns rapidly in the presence of oxygen
Testing for oxygen:
➢ Insert a glowing splint into a test tube containing a gas
➢ If the gas is oxygen the splint will relight
Testing for carbon dioxide:
➢ Bubble through or shake carbon dioxide with lime water
➢ The solution will turn from clear to cloudy
Oxidation and reduction:
➢ OIL RIG
➢ Oxidation is loss
➢ Reduction is gain
Energy transfer:
➢ Energy is transferred in reactions, not created or destroyed
➢ Endothermic reactions- energy from the surroundings is transferred to the reacting
chemicals causing the temperature of the surroundings to decrease
➢ Exothermic reactions- energy from the reacting chemicals is transferred to the
surroundings, increasing the temperature
Requirements for a reaction to happen:
➢ Collisions- reacting particles must collide
➢ Activation energy- collisions must take place with sufficient energy for a reaction to
occur
Reaction profiles: exothermic to endothermic
Catalysts:
➢ Can increase reaction rates by increasing the likelihood of successful collisions. They
achieve this by lowering the activation energy
Chemical bonds:
➢ Measures the strength of chemical bonds
➢ Total bond energy of the product - total bond energy of the reactants
, ➢ Measured in KJ.mol
➢ Bond making is exothermic
➢ Bond breaking is endothermic
Chemical cell:
➢ Batteries & cells contain chemicals that react to produce electricity
➢ Can be produced by connecting 2 different electrodes and putting them in a liquid
electrolyte
Fuel cells:
➢ Produces electrical energy
➢ Uses a reaction between hydrogen and oxygen. Fuel is added to the cell and then there’s
a constant supply of oxygen. This fuel is oxidised and creates a voltage
➢ Advantages of this are it’s compact and lightweight, reliable, less pollution and highly
efficient
➢ Disadvantages are it has to be stored at high pressure and is explosive
➢ Anode- hydrogen molecules= hydrogen ions + electrons
➢ Cathode- hydrogen ions + oxygen molecules= water
Greenhouse effect:
➢ Greenhouse gases keep the earth warm. Can cause global warming if it becomes too
strong
➢ Sun emits radiation that enters the atmosphere towards the earth. Earth absorbs some of
the radiation and reflects the rest back into the atmosphere. Greenhouses gases absorb
this radiation and re-radiate the energy in all directions increasing the earth’s
temperature
Human activity and greenhouse gases:
➢ Landfill- sites are increasing. More waste is decomposing and decomposition releases
methane
➢ Agriculture- animals release methane during digestion
➢ Deforestation- less trees means less photosynthesis which means less carbon dioxide is
being removed from the atmosphere
➢ Burning fossil fuels- releases carbon dioxide
Global climate change:
➢ Melting polar ice caps- causes sea levels to rise which cause flooding and erosion of
coastal regions
➢ Natural events- severity of extreme events such as storms, heatwaves and droughts
➢ Water availability- changes in water availability could affect species distribution
