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All about chemical formulae. modified internet version. ;. Student guide to writing chemical formulae. Rules leading to correct formula. 1. Positive ions (cations) can join to negative ions (anions). 2. Positive ions usually form the first part of the name (99% cases).
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All aboutchemicalformulae modified internet version
; Student guide to writing chemical formulae
Rules leading to correct formula 1. Positive ions (cations) can join to negative ions (anions) 2. Positive ions usually form the first part of the name (99% cases) 3. If the formula is correct there is no overall charge 4. If you have more than one polyatomic ion it is placed inside brackets
Essential training ions Positive ions (Cations) Negative ions (Anions) - 1 + 1 fluoride F- sodium Na+ potassium K+ chloride Cl- hydrogen H+ bromide Br- lithium Li + hydroxide OH- silver Ag+ nitrate NO3- ammonium NH4+ hydrogencarbonate HCO3- +2 magnesium Mg2+ - 2 carbonate CO32- calcium Ca2+ oxide O2- barium Ba2+ sulphide S2- zinc Zn2+ sulphate SO4 2- iron(11) Fe2+ sulphite SO3 2- copper Cu2+ 2- chromate CrO4 - 3 +3 aluminium Al3+ nitride N3- chromium Cr3+ 3- phosphate PO4 iron(111) Fe3+
Chemical Formulae 1. sodium fluoride CHARGES IONS NUMBERS FORMULA
magnesium fluoride other examples silver hydroxide calcium nitrate ammonium carbonate MgF2 (NH4)2CO3 AgOH Ca(NO3)2
other examples aluminium bromide chromium sulphide AlBr3 Cr2S3