1. Noadswood Science, 2012

2.  To know how atoms form ions Sunday, June 26, 2016

3.  How heavy is an atom?  A single grain of sand contains millions of atoms of silicon and oxygen joined together – therefore the mass of an individual atom must be extremely small…

4.  Atoms are so small that their mass is not measured in grams but in atomic mass units  The atoms of each type of element have a relative atomic mass (RAM) or A r  The element carbon is the atom that the mass of all other atoms is compared to – carbon has a RAM of 12 Carbon RAM = 12

5.  The lightest atom is hydrogen – it has 1 ⁄ 12 the mass of carbon and so has a RAM of 1  Magnesium is twice as heavy as carbon – it has a RAM of 24

6.  What is the mass of one carbon atom? 1 carbon atom = 12 amu (atomic mass units) 1 carbon atom = 0.00000000000000000000001993 grams  *Remember there are also the subatomic particles: neutrons, protons and electrons which are even smaller: -  Neutron = 1 amu  Proton = 1 amu  Electron = 1/2000 amu

7.  What charge do atoms usually have – why is this?  Neutral atoms have no overall charge – this is because the charge of the electrons is the same as that of the protons, just opposite  A neutral atom has no charge as the number of protons equals the number of electrons  However, sometimes the charges can vary, in which case the atom is no longer regarded as neutral…

8.  Ions are electrically charged particles formed when atoms loose or gain electrons  This loss or gain leaves a complete highest energy level, so the electronic structure of an ion is the same as that of a noble gas - such as a helium, neon or argon +ve (cation) -ve (anion)

9.  Metal atoms and non-metal atoms go in opposite directions when they ionise…  Metal atoms lose the electron, or electrons, in their highest energy level and become positively charged ions  Non-metal atoms gain an electron, or electrons, from another atom to become negatively charged ions

10.  There is a quick way to work out what the charge on an ion should be…  The number of charges on an ion formed by a metal is equal to the group number of the metal  The number of charges on an ion formed by a non-metal is equal to the group number minus eight (hydrogen forms H + ions)

11. *Carbon and silicon (group IV) usually form covalent bonds (sharing electrons) **Elements within group VIII do not react with other elements to form ions IIIIIIIVVVIVIIVIII Element example NaMgAlCNOClHe Charge 1+2+3+*3-2-1-** Ion symbol Na + Mg 2+ Al 3+ *N 3- O 2- Cl - **

12. Atomic Zoom

13. Subatomic

14. Anagrams