Chemistry - year 8

• Element


  A pure substance made of only one kind of atom
• States of matter


  solid, liquid, gas, (aqueous)
• Solid


  Compact, fixed positions, regular, low energy, not easily compressed
• Liquid


  Irregular arrangement, no clearly designed shape, take on shape of container, some energy - little movement, can be compressed to a certain degree
• Gas


  No clearly defined shape, no touching particles, lots of energy, lots of random movement, can be compressed
• Solid to liquid


  melting
• Liquid to solid


  freezing
• Liquid to gas


  evaporating
• gas to liquid


  condensing
• Solid to gas


  subliming
• gas to solid


  deposition
• Example of a substance that sublimes


  Iodine
• Physical change is...


  A change that doesn't alter the chemical properties of the matter
• Chemical change is...


  The breaking or forming of bonds between molecules or atoms, making at least one new substance
• Testing for hydrogen


  What procedure is this? (squeaky pop)

  
• Testing for carbon dioxide


  What procedure is this?

  
• Word equation for the production of oxygen

  hydrogen peroxide + (manganese (IV) Oxide (Powder)) - Catalyst > water + oxygen
• Word equation for the production of hydrogen

  Magnesium + hydrochloric acid > magnesium chloride + hydrogen
• Word equation for the production of carbon dioxide

  Carbon dioxide + calcium hydroxide > calcium carbonate + water
• Balanced symbol for the production of oxygen

  2H2O2(aq) > 2h2O(l) + O2(g)
• Balanced symbol for the production of hydrogen

  Mg(s) + 2HCl > MgCl2(aq) + H2(g)
• Balanced symbol for the production of carbon dioxide


  CO2(g) + Ca(OH)2 > CaCO3(aq) + H20
• Write the balanced word equation for the chemical reaction between hydrogen and oxygen in the test for hydrogen gas

  2Hydrogen + oxygen > 2H2O
• Write the balanced symbol equation for the chemical reaction between hydrogen and oxygen in the test for hydrogen gas

  2H + O > 2H2O
• What is the 'cloudiness' in calcium carbonate?

  A precipitate
• What is the the explosive symbol put on?


  A chemical that can explode
• What is the the oxidising symbol put on?

  An oxidising agent that can cause other things to catch fire.
• What is the the toxic symbol put on?

  Chemicals that are poisonous.
• What are some rules for an element symbol?

  Must begin with a capital letter, second letter has to be lower case, 1 or 2 letters, no numbers
• What is the symbol for Lithium?


  Li
• What is the chemical symbol for Curium?

  Cm
• What is the chemical symbol for tungsten?

  W
• What are some elements that are gases?

  Hydrogen, Helium, xenon
• What are the elements that are liquid at room temperature?

  Mercury, bromine
• What is a physical property?


  a characteristic that can be observed or measured without changing the identity of the substance
• What is an example of a physical property?

  Melting temperature, how it dissolves in water
• What is a chemical property?

  How a substance reacts
• What is an example of a chemical property?

  flammability
• Define the word atom

  The smallest particle of which everything is made
• Define the word element


  Substances that are only made of one type of atom