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Chemical formulae ∙ Tātai matū. A chemical formula is a representation of how many atoms are in a substance. E.g. Cl. H. H Cl. Hydrogen Chloride. -. -. -. -. -. -. -. -. -. -. -. -. -. -. -. -. -. -. 1 Hydrogen atom; 1 Chlorine atom. 0 overall charge. Other examples.
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Chemical formulae ∙ Tātaimatū A chemical formula is a representation of how many atoms are in a substance. E.g. Cl H HCl Hydrogen Chloride - - - - - - - - - - - - - - - - - - 1 Hydrogen atom; 1Chlorine atom 0 overall charge
Other examples O Small ‘subscript’ numbers tell us the amount of atoms for the atom to the left. E.g. O4 = Oxygen x 4 H2SO4 O S O H H Hydrogen Sulfate O 1 Hydrogen atom; 2 Sulfur atoms; 4 Oxygen atoms 0 overall charge
Other examples O Small ‘superscript’ numbers tell us the overall charge. E.g. 2- = two extra electrons SO42- O S O [ ] 2- Sulfateion O 1Sulfur atom; 4 Oxygen atoms 2- overall charge
Other examples Metal + Non-metal = Ionic bond NaCl Sodiumchloride Na+ Cl- 1Sodium ion; 1 Chloride ion 0overall charge