See pages Magnesium bromide Potassium oxide Calcium chloride

3 Names of Some Common Ions Copyright © 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings

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Criss-Cross Rule

Try These Ca & Cl S & Al Na & H Ca 2+ O 2- CaCl 2 Al 2 S 3 NaH CaO Remember, the location of numbers is VERY important The subscript (lower) is the number of atoms The superscript (upper) is the charge on the ion If they are in the wrong place and not reduced they are WRONG – no part marks

See pages Example 1: Sometimes when iron combines with oxygen forms a black compound Iron II oxide (FeO = Iron II oxide) Example 2: Sometimes when iron combines with oxygen forms a rust-coloured compound Iron III oxide (Fe 2 O 3 = Iron III oxide)

Example 1) Gold (I) chloride Au +1 Cl -1 AuCl 2) Lead (IV) oxide Pb +4 O -2 PbO 2

Na(CO 3 ) Ca(OH) Na 2 (CO 3 ) Ca(OH) 2 Example: Compound formed with Na and CO 3 would be… Example: Compound formed between Ca and OH would be…

Predict the compound formed from: Na + and OH - Mg 2+ and NO 3 - NH 4 + and SO 4 2- Na(OH) Mg(NO 3 ) 2 (NH 4 ) 2 SO 4

Predict the compound name: Ca(CO 3 ) K(CN) Ca 3 (PO 4 ) 2 (NH 4 )F Calcium carbonate Potassium cyanide Calcium phosphate Ammonium Fluoride

Iron (II) hydroxide

Types of Chemical Reactions Exothermic – energy is released from the reaction Example: Atomic blast Memory Tip: –Exo – starts with the letters “ex” similar to exit

Types of Chemical Reactions Endothermic – energy is absorbed in order for the reaction to occur Example: cooking eggs Memory Tip: –Endo – starts with the letters “en” similar to enter

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