elements, compounds and isotopes

• Elements consist of atoms with the same atomic number
• The number of protons in the nucleus decides what type of atom it is.
• Isotopes are different forms of the same element that have the same amount of protons with a different number of neutrons.
• What do isotopes have a different number of?

  neutrons
• Isotopes have the same atomic number but different mass numbers.
• Is an isotopes atomic number or mass number different?

  mass number
• Carbon twelve and carbon 13 are examples of what?

  isotopes
• Why do we calculate relative atomic mass?

  because of isotopes
• Relative atomic mass is a what?

  average mass taking into account different masses and abundances of isotopes
• How do you calculate relative atomic mass?

  sum of (isotopes abundance x isotopes mass number)/sum of abundances of all the isotopes.
• Atoms join together to make compounds
• A compound formed between a metal and a non-metal consists of ions.
• A compound formed from a non-metal and a non-metal consists of molecules.
• Ionic bonding is between a metal and a non-metal.
• Covalent bonding is between two non-metals.
• What is ionic bonding between?

  A metal and a non-metal
• What is covalent bonding between?

  A non-metal and a non-metal
• A formula shows what is in a compound.
• What is the formula for ammonia?

  NH3
• What is the formula for calcium chloride?

  CaCl2
• What is the formula for sodium carbonate?

  Na2CO3
• What is the formula for sulfuric acid?

  H2SO4
• An atom is the smallest part of an element that can exist.
• There is only one type of atom in an element.
• A molecule is a particle that contains 2 or more atoms joined together.
• Name some examples of molecules.

  O2

  N2

  Cl2

  H2
• Name some giant structures.

  Carbon

  iron

  copper

  sodium
• A compound is two or more elements chemically combined in fixed proportions.
• An atom is the smallest part of an element that can exist.
• An element is one type of atom.
• A molecule is a particle that contains 2 or more atoms joined together.
• A giant structure is usually a solid.
• Name common molecules.


  02

  N2

  Cl2

  H2
• Name some common giant structures.

  carbon

  iron

  copper

  sodium
• A compound is..


  two or more elements chemically combined in fixed proportions.