IONS AND IONIC COMPOUNDS IONS AND IONIC COMPOUNDS • MONATOMIC IONS MONATOMIC IONS are atoms with a are atoms with a positive or negative charge. positive or negative charge. • Taking away Taking away an electron from an atom an electron from an atom gives a gives a CATION CATION with a with a positive positive charge charge • Adding Adding an electron to an atom gives an an electron to an atom gives an ANION ANION with a with a negative charge negative charge . .
IONS AND IONIC COMPOUNDS. MONATOMIC IONS are atoms with a positive or negative charge. Taking away an electron from an atom gives a CATION with a positive charge Adding an electron to an atom gives an ANION with a negative charge .. PREDICTING ION CHARGES. In general - PowerPoint PPT Presentation
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IONS AND IONIC COMPOUNDSIONS AND IONIC COMPOUNDS
•MONATOMIC IONSMONATOMIC IONS are atoms with a are atoms with a
positive or negative charge. positive or negative charge.
• Taking awayTaking away an electron from an atom gives a an electron from an atom gives a
CATIONCATION with a with a positive chargepositive charge
• AddingAdding an electron to an atom gives an an electron to an atom gives an ANIONANION
with a with a negative chargenegative charge..
PREDICTING ION CHARGESPREDICTING ION CHARGESPREDICTING ION CHARGESPREDICTING ION CHARGES
• nonmetalsnonmetals (F) (F) gain electronsgain electrons ---> ---> anionsanions
– Charge = group number -8Charge = group number -8
Charges on Charges on Common IonsCommon IonsCharges on Charges on
Common IonsCommon Ions
+3
-4 -1-2-3+1
+2
By losing or gaining e-, atom has same By losing or gaining e-, atom has same number of e-’s as nearest Group 8A atom.number of e-’s as nearest Group 8A atom.
METALSMETALSM ---> n e- + MM ---> n e- + Mn+n+
where n = periodic groupwhere n = periodic groupNaNa++ sodium ionsodium ionMgMg2+2+ magnesium ionmagnesium ionAlAl3+3+ aluminum ionaluminum ion
Transition metalsTransition metals -->M -->M2+2+or Mor M3+ 3+ are commonare common
• Binary compounds are composed of two elements, a metal and a non-metal.
• Place the name of the cation first and then the name of the anion.– Remember the –ide suffix.
chlorideSodiumThe cation The anion
Writing formulas for Binary Ionic Compounds
• Write the symbol of the cation and the anion (include the charge)
• Add whatever subscripts are needed to balance the charge
• Use the criss-cross method– The charge of one ion becomes the subscript of
the other. Don’t forget to reduce to the empirical formula.
Naming Ternary Ionic Compounds
• Ternary compounds are composed of three or more elements.
• Place the name of the cation first and then the name of the anion.
• Often end in –ite and -ate
StrontiumThe cation
sulfateThe polyatomic ion. Don’t change the name
Writing formulas for Ternary Ionic Compounds• Write the symbol of the cation and the
anion (include the charge)• Add whatever subscripts are needed to
balance the charge• Use parentheses when the compound
contains more than one polyatomic ion• Use the criss-cross method
Naming Binary Molecular Compounds
• Binary compounds are composed of two elements, two non-metals.
• The name identifies the elements and how many of each atom there is in the compound.
• Name the elements in the order they appear in the formula.• Use prefixes to indicate the number of each kind of atom.• Omit mono- when the name has only one atom of the first
element.• Use the suffix –ide for the name of the second element.
9.3
Naming Binary Molecular Compounds
Name these compounds!
• PBr3
• CrBr3
• N2O
• Na2O
• Cl4
• PbI4
• P2O3
• Fe2O3
Writing formulas for Binary Molecular Compounds
• Use the prefixes in the name to determine the subscript of each element in the formula.
Phosphorus pentafluoride
Naming Acids
• Ionic compounds with unique properties
• Contain one or more hydrogen atoms and produce H+ ions when dissolved in water
1. When the name of the anion ends in –ide , the acid name begins with hydro-. The stem of the anion has the suffix –ic and is followed by the word acid.
HCl hydrogen chloride
acid name – hydrochloric acid
2. When the anion name ends in –ite, the acid name is the stem of the anion with the suffix –ous, followed by the word acid.
H2SO3 hydrogen sulfite
Acid name – sulfurous acid
3. When the anion name ends in –ate, the acid name is the stem of the anion with suffix –ic followed by the word acid.
HNO3 hydrogen nitrate
Acid name – nitric acid
Naming Bases
• Ionic compounds with unique properties
• Produce OH- ions when dissolved in water
• Named the same as other ionic compounds – Name of the cation followed by the anion.