naming ionic compounds
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Naming Ionic Compounds. Transition Metals and Polyatomic ions. Remember:. No prefixes !!!!!! Write the name of the metal. Write the name of the non-metal. Change the ending of the non-metal to “ide” Ex: NaCl sodium chloride. Transition Metals:. - PowerPoint PPT PresentationTRANSCRIPT
Naming Ionic Compounds
Transition Metals and Polyatomic ions
Remember:
• No prefixes !!!!!!
1. Write the name of the metal.2. Write the name of the non-metal.3. Change the ending of the non-
metal to “ide”Ex: NaCl sodium chloride
Transition Metals:• Nearly all the transition metals are
able to form more than one cation or are multi-valent.
• Ex: iron can form Fe2+ and Fe3+. Given the formula of an ionic compound you can use the reverse cross-over method to determine the charge of the cation. Ex: FeCl3
Stock System:
• The charge of the cation is written in parentheses as a roman numeral. Ex: Fe3+ would be iron (III) and Fe2+ would be iron (II).
• Remember roman numerals: 1-(I), 2- (II), 3-(III), 4-(IV), 5-(V).
Example:• Both CuO and Cu2O are real compounds• We know that O always has a charge of
-2
• For CuO, we know that it is the Cu+2 ion (sum to zero)
copper (II) oxide
• And for the Cu2O, we know that there is 2 x the Cu+1 ion (to sum to zero)
copper (I) oxide
Try to write names for these (don’t forget the roman numberial for the metal) :
• CrO
• Au3P
• SnCl4
Given the name we can write the formula:• Nickel (III) bromide• We know that Br is always Br-1
• We also know that this is the Ni3+ ion (it tell us in the brackets)
• Therefore we need 3 x Br-1 with Ni3+ for the compound to be neutral (sum
to zero) NiBr3
Try these:
• lead (II) chloride
• mercury (I) arsenide
• cobalt (II) chloride.
Polyatomic Ions
• Have a charge ( + or - )• Consists of two or more non-metal
atoms (or metal complex) joined by a covalent bond
• Act as a single unit
Write names for ionic compounds containing polyatomic ions:
• Na2CO3
• KOH
• Sn3(PO4)4
Writing chemical formulas for ionic compounds containing polyatomic ions: (remember to use parentheses to indicate the correct number of ions)
1. ammonium sulfide
2. lead (IV) hydrogen carbonate
3. calcium hydroxide
4. magnesium nitrate
Practice: handout