Chapter 9

• What is an empirical formula?

  Formula that shows the lowest whole number ratio of elements in a compound
• What is a molecular formula?

  A formula that shows the true ratio of elements in a compound
• Molecular and empirical formula can be the same.
• What is a condensed formula?

  Formula showing the relative numbers of atoms
• What is a structural formula?

  Forumla that shows the way atoms are joined in a molecule
• What are isomers?

  Compounds with the same ratio of atoms, attacthed in a different order
• What is the rule for writing the formulas of binary ionic compounds?

  If the charges are the same, dont do anything, if they're different, criss cross them
• What is a chemical formula?

  Notation that shows the relative number of atoms in a molecule
• What is the rule for ternary ionic cocmpounds?

  If you use a polyatomic ion more than once you have to put parantheses around it
• IN which type of molecule do you have to write the (II) and (I)?

  Ionic compounds - for the special metals only
• Ag is always what charge?

  +1
• Zn is always what charge?

  +2
• With ions, do you do stock systems or the prefixes?

  No, only if it is one of the special metals (cu, fe, etc)
• What are the special metals that change their stock system?

  Iron, tin, lead, copper, and mercury
• What are the latin names for the special metals?

  Iron: Ferrum, Tin: Stannum, Lead: Plumbum, Copper: Cuprum, Mercury: Mercury
• What are the possible charges of iron?

  +2, +3
• What are the possible charges of tin?

  +2, +4
• What are the possible charges of lead?

  +2, +4
• What are the possible charges of copper?

  +1, +2
• What are the possible charges of mercury?

  +1, +2
• If it is the high charge of the 2 possible charges of the special metal, what does the ending become?

  -ic
• If it is the low charge of the 2 possible charges of the special metal, what does the ending become?

  -ous
• What is another word for covalent?

  moelcular
• When you're doing bonds for covalent molecules, what are the 2 ways you can do it?

  Traditionally with prefixes, or with the stock system
• When doing covalent bonds, can you use the stock system on any molecule?

  Yes - that is instead of the prefix. For ionic bonds, it's only for the special metals because ionic bonds dont have the -di or -tri things
• What is the strategy for naming chemical formulas?


  Covalent: this is where you do prefixes and stock system (between nonmetals)Acids: things with H, binary acids add hydro to the front, ternary makes -ate to ic and -ite to -ous Ionic: latin words, stock system with (III)
• What is an oxidation number?

  A number assigned to an atom to show the distribution of electrons; also the number that the atom can be that isn't its definite charge
• What is the oxidation number of free elements?

  0
• What is the oxidation number of ions?


  the charge of that ion
• What is the oxidation number of F?

  -1
• What is the oxidation number of O?

  -2, except in peroxides it's -1
• What is the oxidation number of H?

  +1, except in metal hybrides where it is -1
• When assigning oxidation nubmers, the more electronegative atoms gets a

  negative charge
• What number do oxidation numbers add up to in compounds?

  0
• In PAI, what is the ox #?

  the charge of that polyatomic ion
• What is a base?

  Ionic compounds are bases
• What are acids?

  When a solution yields H+ ions in solution
• What are the types of acids?

  binary and ternary
• What is a binary acid?

  H and one other type of atom, they are named by saying hydro____ic acid.
• What are the rules when wrtiing acids?

  criss cross applesauce rules