• Question: how many atoms are used in different elements and how do you know that many atoms are in a element like for exaple carbon dioxide how many element would that have and how would you know

    Asked by littlemissknowitall to Antonia, Douglas, Hugh, Matt, Tom on 22 Jun 2010 in Categories: .
    • Photo: Douglas Blane

      Douglas Blane answered on 22 Jun 2010:


      OK, each element has its own kind of atom. So carbon is made of carbon atoms. Oxygen is made of oxygen atoms.

      What makes it a carbon atom? It’s the number of protons it has – which is usually also the same as the number of electrons.

      So if you get an atom that has 8 electrons and protons, that’s an oxygen atom. Get one with 6 electrons and protons it’s a carbon atom.

      Now if you have loads of carbon atoms in one place you’ve got the element carbon. Loads of oxygen atoms in one place that’s the element oxygen.

      Now carbon atoms can join with oxygen atoms to give you a molecule. What’s it called? Carbon dioxide.

      If you get loads of carbon dioxide molecules in one place then you have carbon dioxide.

      Anything that’s made of atoms joined into molecules, and then loads of molecules collected together, is called a compound. Most of the things around you – like salt and water – are compounds.

      There are elements around us as well. The oxygen in the air and the iron in a hammer are elements They’re only made of one kind of atom. Compounds have more than one kind of atom joined together.

      So how do we know? Well you can combine carbon and oxygen – by burning coal for instance – and you find you get carbon dioxide.

      You can also start with a compound – like carbon dioxide or water – and split it into the elements it’s made from.

      If you pass an electric current through water, for instance, you get hydrogen and oxygen – the two elements water is made from – coming off. This happens because each water molecule gets split by the electric current into separate hydrogen and oxygen atoms.

      I hope this helps.

    • Photo: Antonia Hamilton

      Antonia Hamilton answered on 22 Jun 2010:


      the chemical formula tells you. for example, C02 has one carbon atom and two oxygens.

    • Photo: Matthew Hurley

      Matthew Hurley answered on 22 Jun 2010:


      Each element consists of one atom, it’s atomic number is on the periodic table – it’s weight is determined by it’s atomic mass, the other number on the table. The atom consists of electrons, protons and neutrons – the number of each determines which element it is.

Comments