Chemistry Test #2

• A substance is oxidized when its oxidation number is increased in a reaction.
• A substance is reduced when its oxidation number is decreased in a reaction.

Independent structure consisting of 2 or more atoms chemically bound together.

Matter composed of 2 or more elements that are chemically bound.

• Total mass of substances does not change during chemical reaction.
• Matter cannot be created or destroyed.

• Compounds are composed of the same element in the same part (fractions) by mass.
• Divide mass of each element by total mass of compound.

2 elements (typically 1 metal, 1 nonmetal) where each metal loses an electron and the nonmetal gains an electron.

Cation or Anion derived from a single atom

• The energy of attraction/ repulsion btwn 2 particles is directly proportional to the product of charges and inversely proportional to distance btwn them.
• 1. Ions w/ higher charges attract/ repel more strongly than lower charges
• 2. Smaller ions attract/ repel more strongly b/c the disance btwn charges is shorter

Pairs of atoms that are chemically bound and behave as an independent unit.

2 or more atoms bonded covalently and have a net positive or negative charge.

Hydrogen

Lithium

Sodium

Potassium

Cesium

Silver

Aluminum

Magnesium

Calcium

Strontium

Barium

Zinc

Cadium

Hydride

Flouride

Chloride

Bromide

Iodine

Oxide

Sulfide

Nitride

• 1) Convert percentages to grams
• 2) Do ratios for grames to moles
• 3) Divide by smallest #
• 4) Write formula with subscripts
• 5) All subscripts must be integers- adjust as necessary

• 1) Convert % to grams
• 2) divide grams by element's amu
• 3) convert from grams to mole (no math)
• 4) divide each answer by smallest
• 5) add amus of empirical formula
• 6) divide molecular weight/ amus
• 7) multiply empirical formula by total from #6

Shows number of atoms and bonds between them.

cation ending for metal names

anion ending for nonmetal

• 1) Cation name first
• 2) add -ide to nonmetal
• 3) place anion last

• Refers to element preceding it
• the subscript '1' is implied from symbol
• The charge of one ion becomes he superscript of the other

• Those in which an elment, usually nonmetal, is bonded to one or more oxygen atoms.
• More 0 atoms- ate
• Less O atoms - ite

Ammonium

Hydronium

Acetate

Acetate

Chlorite

Perchlorate

Cyanide

Hydroxide

Chlorate

Nitrite

Permanganate

Hydrogen Carbonate

Carbonate

Chromate

Dichromate

Phosphate

Peroxide

Hydrogen Phosphate

Sulfite

Sulfate

Hydrogen Sulfate

Sum of Atomic Masses

• Substances that react during change.
• Placed to LEFT of arrow

• All substances produced.
• Placed to RIGHT of arrow.

Bonds with Group 7AMakes a salt

Bonds with group 6AForms a salt

Molecules with same chemical formul but different structural formulas

I would rather be surrounded by water.

Chemical formula and Periodic table

• 1) Find % Composition then Empirical Formula2) Molecualr Weight or
• molar Mass

No Change even with mixutre

• 1) Gain in Oxygen
• 2) Loss of
• 3) Loss of Electrons

LEO

• 1) Loss of Oxygen
• 2) Gain of Hydrogen
• 3) Gain of Electrons

GER

• 1) write compounds largest to smallest moving across table
• 2) go from top to bottom in case of a tie

• 1) Convert % to grams
• 2) Divide gramst by element's amu
• 3) Convert from g to mole (no math)
• 4) Divide each answer by smallest
• 5) Add amus of Empirical Formula
• 6) Divide Molecular Weight/ amus
• 7) Multiply empirical formula by total from #6

Brown Liquid

soL₂id

• Lose electrons easily
• positive ions

gain electrons, for negative ions

• IA-IIIA= +1-+3 respectively, electrons lost = to group number
• IB-IIB= electrons lost = group #
• IIIB-VIIIB= +2 or +3
• Max # of electons gained by nonmetals- 8-group #

Sum of the masses of the atoms

• Do not produce ions in solution and do not yield conducting solutions
• Alcohol, sugar, water

• Dissociate or ionize 100% in aqueous solution
• Yield very conducting solutions at reasonable concentrations.
• Salts, strong acids, strong bases

Ions already exist, water allows them to 'drift apart

Ions don't already exist. polar compounds have 'tendency to form ions

• All have a number of 0
• For single atom, O.N. is = to charge of ion

• H+
• Unless in metal hydride (NaH-, CaH2-), then it is -1

• -2
• Unluss O is peroxide (H2O2, NA2O2), Then it is -1

• Atomic Nuclei are unstable
• Nucleus is not balanced and there is continuous change
• Usually rare metals

• Boron
• Metalloid

• Silicon
• Metalloid

• Arsenic
• Metalloid

• Tellurium
• Metalloid