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• Photosynthesis


  The process by which plants use sunlight, water and carbon dioxide to create oxygen and energy in the form of sugar

  
• Reactants of photosynthesis


  • Carbon dioxide
  • Water

  
• Products of photosynthesis


  • Carbohydrate (glucose)
  • Oxygen

  
• Carbon dioxide


  • Gas present in the atmosphere which is absorbed by plants to make carbohydrates
  • Its role in photosynthesis can be tested by checking for starch production

  
• Water


  • Essential component for plants
  • Enters plants through roots, stem and leaves

  
• Light


  • Sunlight is the main source of energy for plants
  • Its role in photosynthesis can be tested by checking for starch production in covered and uncovered parts of a leaf
• Chlorophyll


  • Green pigment that colours a plant green
  • Its role in photosynthesis can be tested by checking for starch production in green and white parts of a variegated leaf

  
• Carbohydrate


  • Glucose is the main product of photosynthesis
  • Excess glucose is stored as starch

  
• Plants placed under sunlight produce bubbles of gas
• The gas collected relights a glowing splint, showing that the gas is oxygen
• Mineral salts important for plant growth

  • Nitrogen
  • Phosphorus
  • Potassium
  • Magnesium
• Nitrogen


  • Needed for development of leaves and making chlorophyll and proteins
  • Deficiency causes yellow leaves and poor growth

  
• Phosphorus


  • Needed for development of roots, photosynthesis and respiration
  • Deficiency causes poor growth
• Potassium


  • Needed for development of flowers and fruits, and making chlorophyll and proteins
  • Deficiency causes yellow and abnormal leaves
• Magnesium


  • Needed for making chlorophyll
  • Deficiency causes yellow leaves
• Water


  • Provides support to plant cells
  • Transports mineral salts
  • Cools the plant through transpiration
  • Small proportion used in photosynthesis

  
• Fossil Fuels


  • Petroleum
  • Natural gas
  • Coal
• Formation of Fossil Fuels

  1. Petroleum

  2. Natural gas

  3. Coal

  
• Non-renewable Energy


  • Fossil Fuels

  
• Renewable Energy


  Differentiated from Non-renewable Energy
• Generating electricity from different sources

  1. Wind

  2. Water

  3. Sun

  4. Biomass

  5. Nuclear
• Nuclear Energy


  • Energy in the nucleus (core) of an atom
  • Can be released from atoms through nuclear fusion (combining) and nuclear fission (splitting)
  • Nuclear power plants use nuclear fission to produce electricity
  • No carbon emissions
  • Reactors use uranium, not fossil fuels
• Density formula


  Density = Mass / Volume
• Mass formula


  Mass = Density x Volume
• Volume formula


  Volume = Mass / Density
• Group


  Vertical column in the periodic table
• Period


  Horizontal row in the periodic table
• Groups in the periodic table

  • Alkali Metals
  • Metals
  • Non-Metals
  • Alkaline Earth Metals
  • Transition Metals
  • Basic Metals
  • Metalloids
  • Non-metals
  • Halogens
  • Nobel Gases

  
• Periodic Table


  • Identifies groups and periods

  
• Electronic structure of Group 1 Elements


  Meaning not provided
• Group 1 Elements


  • Lithium, Li
  • Sodium, Na
  • Potassium, K
• Trend in boiling point of Group 1 elements
• Boiling point of rubidium

  Lower than 777
• Number of more electrons in sodium than lithium
• Group 1 Elements


  • Size increases, softness increases, melting point and boiling point decreases, and reactivity increases when going down Group 1
• Electronic structure of Group 7 elements


  Meaning not provided
• Halogens are
• Trend in boiling points of Group 7
• Trend in colour in Group 7
• Group 7 Elements


  • Flourine, F
  • Chlorine, Cl
  • Bromine, Br