Accelerated Chemistry Final Exam Review Get Ready to Celebrate!!

Unit 1. Safety and Measurement Mass is the amount of matter in a substance. Weight is the amount of gravity pulling on the object’s matter. Weight can change depending on location, mass can not.

Unit 1 Safety/Measurement 1.Scientific notation - can only have 1 digit to the left of the decimal. 2.Significant Figures - know rules. What digit is the estimated digit? (LAST ONE!) 3. Density, d = m/v 4. Factor Label 5. Basic Safety procedures for lab 6. Rounding Rules >5, round up <5, no change =5 (Number before is even, stays the same) (Number before is odd, round up).

Significant Figures Significant Figures Rules 1. ALL NONZERO integers are significant. 2. Zeros that LEAD a number are NEVER significant. Ex: Zeros that are between other nonzero integers ARE significant. Ex: Zeros at the end of a number are significant ONLY if there is a decimal somewhere in the number. Ex: not sig = 120,000 –Sig = 120, x 105

Metric Conversions 1 mL = 1cm 3

Accuracy vs. Precision Accuracy- The closeness of a measurement to the true value. Precision- The extent to which an experiment can be repeated with the same result.

Physical vs. Chemical Physical Properties that are detected by the senses or can be identified without a chemical reaction. Physical Change does not result in a new substance. Chemical Properties is the ability of a substance to form a new one. Chemical Change results in a totally different substance

Solids - solubility increases as temperature increases. Gases - solubility decreases as temperature increases. Practice solubility graph problems! Unit 2: Solubility

Saturated: A solution in which the solvent has as much solute dissolved in it as possible for that temperature. Unsaturated: A solution in which more solute can be added and dissolved in the solvent. Supersaturated: A solution in which more solute is dissolved than would normally be allowed for that temperature.

Unit 3 Nomenclature/Balancing Atom is smallest part of element that can exist. Atoms have a neutral charge. Ion is an atom or group of atoms that has a + or - charge. Cations are positively charged ions. Anions are negatively charged ions. Monatomic ions have only one type of atom. Polyatomic ions have more than one type of atom.

Ionic compounds consist of a metal and nonmetal. Charges must be neutral. Positive ion first, then negative ion. If more than one charge, must include Roman numeral. Add suffix “ide” to second element. Reduce to lowest terms. (Ex. NaCl, NaOH) Covalent compounds consist of two nonmetals. Not based on charges. Use numerical prefixes (mono, di, tri, etc.) Add suffix “ide” to second element. Cannot reduce. (Ex. CO 2, HF) Ionic vs. Covalent

Calcium chloride Beryllium oxide Aluminum oxide Potassium bromide Lithium phosphide Write the following formulas for Binary Ionic Compounds. CaCl 2 BeO Al 2 O 3 KBr Li 3 P

Lead (II) bromide Copper (I) nitride Iron (II) Chloride Lead (IV) oxide Examples with varying charges PbBr 2 Cu 3 N FeCl 2 PbO 2

Write the names of the following FeF 2 CoCl 2 Cu 2 S NiO Co 3 N 2 CuBr

Synthesis (Composition or Combination )- takes 2 reactants to form 1 product A + B > AB Decomposition- one reactant breaks up into more than one AB ----->A + B 2KClO > 2KCl + 3O 2 Single Replacement (Displacement)- Reactant composed of more than one type of atom gives it’s “Partner” to another reactant. A + BC > AC + B Double Replacement(Displacement)-Reactants composed of more than one type of atom “switch partners” AB + CD > AD + CB Combustion-Reaction of compounds containing C’s & H’s with oxygen to form carbon dioxide and water. Ex: C 6 H 12 O 6 +6O 2 ---> 6CO 2 + 6H 2 O

Unit 4 Stoichiometry Mole Road Map Grams A Moles A Moles B Grams B Liters ALiters B

1. For each element, multiply atomic mass by subscript: H 2 2 x 1.00 = 2.00 O 1 x = Find formula mass: = amu 3. Plug in to percent composition for each. H 2.00 / = % O / = % Percent Composition by Mass

Empirical Formulas Step 1:Convert grams to moles. Step 2: Divide each by the smallest number of moles to get subscripts. Step 3: If you do not have a whole number, or one that is reasonably close, multiply by an integer to obtain a whole number.

Step 1: Find the moles of anhydride (compound without water) Step 2: Find the moles of water. Step 3: Divide moles of water by moles of anhydride. This should turn out to be a whole number Step 4: Place this whole number into the formula in front of water. Empirical Formula for a Hydrate

Hg--> 67.6g x 1mole =.337 moles Hg g S --> 10.8g x 1mole =.337 moles S 32.06g O --> 21.6g x 1mole = 1.35 moles O 16.00g /. 337 = 1 /. 337 = 4 Empirical Formula

Mole-Mole Problem Aluminum and oxygen react to form aluminum oxide. If you have 2.3 moles of aluminum oxide after the reaction how many moles of aluminum were used? 4Al + 3O 2 ---> 2Al 2 O 3

Mole-Mass Problem You have 6.7 moles of oxygen gas reacting with unlimited supply of hydrogen. How many grams of water are produced? H 2 + O 2 ---> 2H 2 O

Mass-Mass Problem CaC 2 reacts with water to produce C 2 H 2 and calcium hydroxide. If 51.6g of CaC 2 are reacted, how many grams of calcium hydroxide are produced? CaC 2 + 2H 2 O ---> C 2 H 2 + Ca(OH) 2

Limiting Reactant The limiting reactant is the reactant that gives you the least amount of product. How will you know if it is a L.R. Problem? --- You will be given 2 amounts of a reactant! Do 2 stoich problems, the one that produces the least amount is the limiting reactant.

Limiting Reactant How many grams of CO 2 can form when a mixture of 2.93g of ethylene and 5.29g of oxygen are reacted? C 2 H 4 (g) + 3 O 2 (g) ---->2 CO 2 (g) + 2 H 2 O(g) O 2 --> 4.85g CO 2 possible C 2 H 4 --> 9.19g CO 2 possible 4.85g CO 2 can be formed based on LR which is O 2.

Limiting Reactant Problems How many grams of lithium nitride can be made by reacting 56.0g of nitrogen with 56.0g of lithium? N 2 + 6Li ----> 2Li 3 N

Theoretical, Experimental, & Percent Yields Theoretical yield is the amount of product that you mathematically determine (using stoich) from a chemical reaction. Experimental yield is the amount of product that you actually get when you perform the reaction in lab. Percent yield = Experimental Yield x 100 Theoretical Yield

Gases 1atm = 760 mm Hg = 760 torr = 101,325 Pa Standard Temperature and Pressure (STP) = 1 atm and 273 K

Mass/Volume STP Consider the following equation: C 6 H 12 O 6 (s) + 6O 2 (g) -----> 6CO 2 (g) + 6H 2 O(g) 1. How many liters of carbon dioxide can be produced when 50.0 of of sugar react with excess oxygen at STP?

Consider the following equation: C 6 H 12 O 6 (s) + 6O 2 (g) -----> 6CO 2 (g) + 6H 2 O(g) If 15.0L of oxygen react with excess glucose at STP, how many grams of water will be produced?

Ideal Gas Law P = PRESSURE (in atm) V= VOLUME (in L) n = MOLES OF GAS R= GAS CONSTANT, L Atm/mol K T= TEMPERATURE (in K)

Gas Stoichiometry If at STP, use stoichiometry. If not at STP, use PV=nRT. 1 mole of any gas = 22.4L