Reactions

• Sorty


  • Sal
  • ocean coater
  • air
• Substances


  • water
  • table salt
  • Sugar
• Reactione


  A chemical change that occurs when two or more substances combine to form a new substance
• When atoms react with other atoms, new materials are formed
• Reactants


  The substances at the beginning of a chemical reaction
• Products


  The new materials made after the chemical reaction has finished
• Chemical reactions occur all around us all the time
• Changes observed during a chemical reaction

  • Colour changes
  • Production of gas
  • Production of heat
  • Loss of heat
  • Production of light
  • Production of a solid (precipitate)
• Precipitate


  An insoluble solid that emerges from a liquid solution
• Reaction between magnesium ribbon and hydrochloric acid

  1. Hydrochloric acid has dissolved the magnesium ribbon

  2. Produced hydrogen gas
• Magnesium is more reactive than copper


  In the reaction with aqueous copper II sulphate, the blue colour of copper sulphate slowly turns reddish brown as a solid is coated on the surface of magnesium
• Since magnesium is more reactive, it displaces copper from the solution
• Eating different parts or at different times of the same organism is known as resource partitioning
• The owl eats at night while the hawk eats during the day
• Mutualism


  When two different organisms work together, both benefiting from the relationship
• Commensalism


  A class of relationship where one organism benefits from the other without affecting it
• Predator


  An organism that eats another organism
• Parasitism


  A non-mutual relationship where one species, the parasite, benefits at the expense of the other, the host
• Plants that have adapted to live on both land and water are found along the edge of the water, as their roots are actually rooted along the edge of the muddy bottom of the lake, river or coast
• Terrestrial plants


  Plants that grow on the land
• Aquatic plants


  Plants that grow in water
• Land plants


  • Have thousands of leaves like a mango tree
  • Have bigger broader leaves to capture more light for photosynthesis
  • Grow taller rather than broader, as their roots anchor them firmly to the ground
• Water plants


  • Have few leaves like water lilies
  • Have thick, spongy leaves that allow the plant to float on the water
  • Are usually broader in shape then they are tall, which also helps with floating
  • Have a single root for each leaf and the roots extend into the water
• Common examples of land plants

  • Hibiscus, pasparo, coconut palms
• Common examples of water plants


  • Water lilies, sedges, reeds
• Our fossil fuel use, coal, oil and gas, has grown so large that its emissions are affecting the natural systems of the earth
• Natural gas is a clean and convenient fuel with advantages over other fossil fuels
• Modern electronics, new materials, telecommunications and common sense are giving us a much wider range of energy options
• Heat energy


  A form of energy that is transferred from a region of higher temperature to a region of lower temperature
• Ways of heat transfer

  • Conduction
  • Convection
  • Radiation
• Conduction


  The transfer of heat within a body or between two bodies that are touching, occurring in solids, liquids, or gases that are at rest
• Convection


  The transfer of heat from one fluid to another by the movement of the fluid itself
• Radiation


  All objects radiate energy and heat, even your own body. Radiation leaves an object in the form of waves, with the hotter an object, the shorter the wave length of this radiation
• Electrical energy


  One of the basic forms of energy, having the property of atomic particles (electrons or protons) being stationary or moving as in an electric current
• Electricity is one of the most convenient forms of energy because it can easily be changed into other forms of energy such as light and heat
• Devices that use electrical energy

  • Computers, televisions, telephones, lights, refrigerators, heaters, air conditioning, video games, alarm systems, clothes washers, routers, and countless rechargeable devices like phones and electronic tablets
• Sound energy


  Produced when an object vibrates, causing the air around the object to vibrate, and these vibrations in the air travel as sound waves
• Solar energy


  Energy that comes from the sunlight, which can be used as both heat energy and electrical energy
• In the 1830s, the British astronomer John Herschel used a solar thermal collector box to absorb sunlight and collect heat to cook food
• Solar energy can be used for heat and electricity, with solar cells used in calculators and to power satellites that orbit the Earth