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Drill: Calculate the % composition of each element in MgN 2 O 3. CHM II HW. Review PP 06 Work the problems attached to Poly’s website. Molar Conversions. Moles. The standard unit of measure for the amount of a substance in numbers. Dozen. = 12 of anything. Moles.
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Drill: Calculate the % composition of each element in MgN2O3
CHM II HW • Review PP 06 • Work the problems attached to Poly’s website.
Moles • The standard unit of measure for the amount of a substance in numbers
Dozen = 12 of anything
Moles = the amount of a substance that would = its mass in g from the PT
Moles = 6.022 x 1023 of anything
Molar Conversions • Mass to moles • Volume of a gas to moles • Particles to moles • Volume of a solution to moles
Mass to Moles • Use atomic masses from the periodic table • NaCl = 58.5 g/mole
Gas Volume to Moles • At STP: 22.4 L/mole • Non-STP: PV = nRT PV RT n =
Particles to Moles • Use Avogadro’s Number • 6.02 x 1023 atoms, molecules, etc/mole
Soln Volume to Moles • Multiply molarity times volume • n = M x V
Solution Measures • Molarity (M) = the number of moles of solute per liter of solution • Others later
Calculate the atomic mass of the element made up of the following isotopes:99.50 % H-10.30 % H-20.20 % H-3
Calculate the atomic mass of the element made up of the following isotopes:5.0 % Pu-242, 5.0 % Pu-24380.0 % Pu-244, & 10.0 % Pu-245
Drill: Determine the volume required to make 60.0 g NaOH into a 0.75 M solution
First Test • Next Thursday on nomenclature, molar conversions, & reactions.
Lowest whole number ratio of elements in a compound • C6H12O6: EF = CH2O
Assume 100 g • Change % directly to grams • Use molar conversions to convert grams to moles • Divide each molar amount by the smallest molar amount
Solving MF from EF 1) Solve empirical mass 2) Divide EM into MM 3) Multiply EF by quotient
Drill: Calculate the mass of solute required to make 40.0 mL of0.25 M Pb(NO3)2
Test Review on Nomenclature, Molar conversions, & % Composition.
Calculate the empirical formula of a substance containing 62.7 % Po, 28.8 % O, & 8.4 % N.
Calculate the molecular formula of a substance with an empirical formula of NH2 & a molecular mass of 32 g/mole.
Name each of the following: • SeO MgS • PbO2 Cl2O • KNO3 ScCl3
Derive formulas for each: • Cesium oxide • Barium chloride • Calcium phosphate • Manganese(II) chlorate
Name each of the following: NH4Cl BaSO4 KC2H3O2 K2HPO3 KNO3 CuBrO Li2CO3 MgC2O4