AP Chemistry Chapters 1-3 Review

Identify complete and balance reactions Synthesis- Two elements combining to form a compound. Remember ionic compounds you must check charges. You should know elements that are diatomic. Example: Aluminum metal reacts with oxygen gas Decomposition A compound is heated and breaks down into two or more products. Know how Carbonates and chlorates beake up. Example: Copper I Carbonate is heated Potassium Chlorate is heated

Identify complete and balance reactions Single Replacement Nonmetal by itself replaces nonmetal in a compound. Example Fluorine gas reacts with sodium oxide Metal by itself replaces metal in acompound. Example: Potassium reacts with aluminum oxide

Identify complete and balance reactions Double Replacement Ionic compounds exchanging ions. Example: Aluminum Nitrate reacts with Potassium carbonate Combustion CxHy + Oxygen gas produces carbon dioxide and water C5H12 reacts with oxygen gas

Polyatomic Ions You should know the following: Nitrate Chlorate Hydroxide All -1 charge Carbonate Sulfate All -2 charge Phosphate All -3 charge All –ite are one oxygen less than –ate Per-ate are one oxygen more than ate. Example: Perchlorate and Sulfite

Limiting and Excess You should be able to solve Limiting –Excess problem such as the one below: 75 grams of Calcium oxide reacts with 125 grams of Aluminum solid Write the complete and balanced reaction Identify the Limiting reagent with calculations Calculate the theoretical mass of Aluminum oxide Calculate the actual yield in the lab if your percent yield was 82.5%

Empirical and Molecular Formulas Find the Empirical and molecular formula of a compound given the following data 1. C= 59.0%, H= 7.1%, O=26.2%, N= 7.7%. The molecular weight of compound is 360 amu 2. A compound with the formula of CxHyOz, when you react 2.00 grams with excess oxygen gas, you produce 3.67 grams of carbon dioxide and 1.00 grams of steam. Given this information calculate the compound’s empirical formula. If the molecular weight of compound is216 amu, calculate its molecular formula.

Hydrate Formula A compound has the following formula MgSO3 XH2O Mass of hydrate 4.00 grams Mass after heating 2.37 grams Calculate the value of X in the hydrate

Protons- Neutrons- Electrons Symbol At. Mass At. # Protons Neutrons Electrons Charge 12 17 +2 42K+1 67 30 31

Significant Figures Calculate the following: A) (25500 X 0.100) /(100X250)= B) (375.55 + 250)/ 0.150= Calculate the density given the following: Mass of beaker + metal 25.55 g +/- 0.02 Mass of beaker 15.15 g +/- 0.02 Volume of water 10.0 +/- 0.1 mL Volume of water + metal 12.5 +/- 0.1 mL Theoretical Density of metal 4.0 g/mL Calculate Mass of metal with % uncertainties. C) Calculate Density with Uncertainties Calculate Volume with % uncertainties D) calculate % error, Random error and Systematic error

Average Mass Given that you have three isotopes of element X, whose average mass is 415.795 Find the % abundance of the isotope of X with a mass of 415, given; that you have three isotopes 414 is 2.5% the other two are 415 and 416

Mass-Moles- Molecules- Atoms Solve the following: 1.50 moles of water to grams 85.6 grams of CO2 to molecules 1.25 grams of HC2H3O2 to atoms of hydrogen 6.15 x1025 formula units of NaF tomass.