Get out your notes and locate the following problem: 896 dL of CO 2 gas contains how many atoms? 2.4e24 Day

Activity Series Lab Day

Propose an activity series based on the following results: A + BY  AY + B A + CY  NO RXN Day A > B C > A CABCAB

CHAPTER QUIZ FRIDAY 10-7!!! Day

Read pages AND complete # 15 on page 361. Day Fe (s) + Pb(NO 3 ) 2(aq)  Fe(NO 3 ) 2(aq) + Pb (s) Ca (s) + 2H 2 O (l)  H 2(g) + Ca(OH) 2(aq) Cl 2(aq) + 2NaI (aq)  2NaCl (aq) + I 2(aq) Zn (s) + H 2 SO 4(aq)  ZnSO 4(aq) + H 2(g)

Percentage Composition Mass of element Mass of compound X (100) = % element in compound … tells how much an element contributes to the mass of the compound

Percentage Composition H 2 O??? 2 H: 2 * g = g 1 O: 1 * g = g g ( g / ) X 100 = % H ( g / ) X 100 = % O

Percentage Composition An unknown compound w/ a mass of g is extracted from the roots of a plant. Decomposition of the sample produces g of C, g of O, and g of H. What is the % composition of the compound?

Day kL of CO gas contains how many grams? How many atoms? 140 grams CO 6e24 atoms

Review (if needed) pages AND complete #s 33, 34, 35, and 36 on pages 326 and 327. Day

Empirical formula – smallest whole- number mole ratio for a compound Empirical Formulas To Calculate: 1. Convert all elements involved to moles 2. Divide all elements by the smallest # of moles 3. Obtain smallest whole #ed ratio

A compound contains 13.5 g Ca, 10.8 g O, and g H. What is the empirical formula? Empirical Formulas 1. Convert all eles. involved to moles 2. Divide all eles. by the smallest # of moles 3. Obtain smallest whole #ed ratio Ca = moles O = moles H =.675 moles Ca = mols / mols = 1 O = mols / mols = 2 H = mols / mols = 2 1 Ca : 2 O : 2 H CaO 2 H 2 Ca(OH) 2

Calculating Empirical Formulas In an unknown compound you find 4.04 g of N and g O. Empirical formula?

67.2 L of CH 4 gas = ___ grams 44.8 mg of solid Carbon = ___ L Day

Homework # 2 = now Postlabs = Friday 10-7 (tomorrow) Presentations = Wednesday Chapter Quiz = Wednesday Day

Empirical formula – smallest whole- number mole ratio for a compound Empirical Formulas vs. Molecular Formulas Molecular formula – actual # of atoms of each ele. in a molecular compound Sometimes But not always! the same.

Molecular Formulas To Calculate: Compare the molar mass of the empirical formula to the molar mass of the molecular formula Molecular formula – actual # of atoms of each ele. in a molecular compound

Determine the molecular formula of the compound with an empirical formula of CH and a formula mass of amu Empirical mass = g/mol x = 6 Molecular formula = C 6 H 6 Determining Molecular Formulas

In an unknown compound you find 4.04 g of N and g O. Empirical formula? This unknown compound has a molar mass of g/mol. What is the molecular formula? Empirical formula = N 2 O 5 Empirical mass = g/mol Molecular formula = N 2 O 5

A sample of a compound contains 6.0 g of C and 16 g of O. The total sample is 22 g. The molecular molar mass is 44 grams Percentage Composition Empirical formula Molecular formula Determining Molecular Formulas

Review section 10.3 (if needed) and complete #s for # 49 the %s can be treated as grams and used to find moles… Assignment due Tuesday 10-11

Calculate the mass of Cu produced? Mass of beaker and Cu – mass of beaker

Calculating percent yield Percent yield – a way to compare how much you “should” get to how much you actually got Percent Yield = Actual yield Theoretic yield X 100

A sample of a compound contains 6.0 g of C and 16 g of O. The total sample is 22 g. Percentage Composition Empirical formula Determining Molecular Formulas Pd. 6

- 2 molar mass convs. - 2 Av.’s # convs. - 2 Av.’s law convs. - 2 multi-step convs. - 1 percentage comp. - 1 empirical formula - 1 molecular formula - 3 content ?s (no math) 14 questions

Mass of element Mass of compound X (100) = % element in compound H 2 O??? 2 H: 2 * g = ________ g 1 O: 1 * ________ g = _________ g (__________________) X 100 = _______% H (___________________) X 100 = _______% O

A compound contains 13.5 g Ca, 10.8 g O, and g H. What is the empirical formula? 1. Convert all eles. involved to moles 2. Divide all eles. by the smallest # of moles 3. Obtain smallest whole #ed ratio Ca = moles O = moles H =.675 moles Ca = mols / mols = 1 O = mols / mols = 2 H = mols / mols = 2 1 Ca : 2 O : 2 H Ca(OH) g Ca 40 g Ca 1 mol Ca 10.8 g O 16 g O 1 mol O g H 1 g H 1 mol H

Percentage Composition Empirical formula Molecular formula