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Starter Question. What is the shape of the following compounds BF 3 OCl 2 NH 4 +. Trigonal planar. Do not hand in homework until you have completed the starter question. You will need it to help you. angular. tetrahedral. What type of bonding occurs in the following compounds
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Starter Question What is the shape of the following compounds BF3 OCl2 NH4+ Trigonal planar Do not hand in homework until you have completed the starter question. You will need it to help you angular tetrahedral What type of bonding occurs in the following compounds Barium Chloride Silicon carbide Dinitrogentetroxide ionic covalent covalent Something that is placed infront of a word. In Chemistry it usually tells us the size of a unit or number of atoms What is a prefix?
Nomenclature Sometimes the name of a compound tells us what its formula is. To work out the formula we need to look for a few things 1. Prefixes 1 2 3 4
When prefixes are used in naming a compound they determine what the formula is and not any other method Using this information can you determine the formula of the following compounds? Carbon monoxide Sulphur dioxide Diphosphoruspentoxide Carbon tertrahydride CO SO2 P2O5 CH4
2. Endings The ending of a compound can tell us which elements are present. ide- ite- ate- This means that only the lements in the name are present in the compound These means that there is a hidden oxygen in the compound
Using this information name the following elements in the following compounds Sodium chloride Carbon tetrahydride Copper sulphate Sodium hydrogen carbonate Sodium chlorine Carbon hydrogen Copper sulphur oxygen Sodium hydrogen carbon oxygen
3. Valencies The valency of an element can be used to determine the formula Remember the valency of an element is different from the number of valence electrons 1 0 3 4 3 2 1 2
The cross- over method for determining formula 1. Write out the symbol of the elements involved in the formula Aluminium oxide Al O 2. Write the valency of each element below it Al O 3 2 3. Cross over the valencies Al O 3 2 2 3
4. If the number have a common denominator divide down e.g. C O 4 2 2 4 ÷2 1 2 5. Write out the formula Al2O3 NB: Remember to use subscripts to show how many of each atom is present in the formula
Now try to determine the formula of the following compounds Magnesium oxide calcium sulphide Calcium nitride potassium oxide
Now complete the worksheets you have been handed. When complete they need to be handed in. When finished please complete questions p221- 226 in the textbook