AP Chemistry Chapter 3 Chemical Quantities (The Mole)

Slides:

Advertisements

Similar presentations

Stoichiometry “In solving a problem of this sort, the grand thing is to be able to reason backward. This is a very useful accomplishment, and a very easy.

Advertisements

Chapter 7- Molecular Formulas

Ch. 7 – The Mole Formula Calculations.

Percent Composition Empirical Formula Molecular Formula

Chemical Quantities or

HOLD UP YOUR BOARD! Chapter 7 Review game.

Chapter 7 Chemical Quantities

What is the % composition of carbon in benzene (C6H6)?

The Mole To play the movies and simulations included, view the presentation in Slide Show Mode X 1023.

Chemical Quantities The Mole.

III. Formula Calculations

Percent Composition Percent = part / whole Example: MgO

HKCEE Chemistry Volumetric Analysis &

What does the little number below each

Molar Conversions (p.80-85, )

IIIIIIIV Ch. 10 – The Mole I. Molar Conversions A. What is the Mole? n A counting number (like a dozen) n Avogadros number (N A ) n 1 mole =

Chemistry Chemical Formulas and Chemical Compounds

Topic 16 Access Code: EC787C089C.

Chapter The Mole 5.6 Molar Mass

Chemical Quantities or

Chemistry I The Mole SAVE PAPER AND INK!!! When you print out the notes on PowerPoint, print "Handouts" instead of "Slides" in the print setup. Also, turn.

Unit 6 - Chapter 12 The Mole.

Chapter 6 Mathematics & Chemical Formulas Unit 7 – The Mole.

Unit 4 – The Mole Honors Chemistry Part 1.

Unit 6 Chapter 12 Chemical Quantities or

Formulas and Percent Composition

The Mole Chapter 6.

Calculations with Elements and Compounds

Stoichiometry Chapter 10 The Mole A counting unit A counting unit Similar to a dozen, except instead of 12, its 602,000,000,000,000,000,000,000 Similar.

Stoichiometry Chapter 12 Notes.

Molar mass, percent composition, empirical and molecular formulas

Moles and Formula Mass.

% Composition, Empirical and Molecular Formulas

Unit 11 Stoichiometry CP Chemistry.

What Could It Be? Finding Empirical and Molecular Formulas.

EMPIRICAL FORMULA The empirical formula represents the smallest ratio of atoms present in a compound. The molecular formula gives the total number of atoms.

All Roads Lead to the Mole

The Mole Concept Chemistry. What is a mole? The mole is a unit used to measure very small quantities – Such as atoms, particles, molecules, ions, etc.

Please pick up the materials in the front and take a seat

The Mole – A measurement of matter

1 Chapter 12 Chemical Quantities. 2 How do you measure things? How do you measure things? n We measure mass in grams. n We measure volume in liters. n.

The Mole: A measurement of Matter

The Mole 1 dozen = 12 1 gross = ream = mole = 6.02 x 1023.

The Mole Molar Mass 0 Also called atomic mass, formula mass, molecular mass 0 Unit = g/mol 0 Calculating Molar Mass 0 Use the average atomic mass from.

Chapter 10 – The Mole The most important concept in chemistry.

The Mole Standards 1 dozen = 1 gross = 1 ream = 1 mole = x There are exactly 12 grams of carbon-12 in one mole of carbon-12.

1 Sherlock Holmes, in Sir Arthur Conan Doyle’s A Study in Scarlet “In solving a problem of this sort, the grand thing is to be able to reason backward.

THE MOLE. Atomic and molecular mass Masses of atoms, molecules, and formula units are given in amu (atomic mass units). Example: Sodium chloride: (22.99.

The mole (abbreviation: mol) is the amount of substance equal to 6.02 x particles These particles can be atoms, ions, formula units,molecules, electrons,

Good Day! 11/23/2015 Starter: = 2! Please explain why this is true. Today we will be… First doing a very thourough cleaning of the lab equipment.

The Mole Standards Standards The Mole 1 dozen = 1 gross = 1 ream = 1 mole = x There are exactly 12 grams of carbon-12 in one mole.

1 The Mole 6.02 X What is “The Mole??” A counting unit (similar to a dozen) 6.02 X (in scientific notation) = 602 billion trillion = 602,000,000,000,000,000,000,000.

Day 33 Notes (Chapter 7) Chemical Quantities (The Mole)

The Mole CA Standards A dozen If I have a dozen eggs, how many is that? 12 If I have a dozen pencils, how many is that? 12 If there are a dozen people.

CHEMICAL QUANTITIES Composition Stoichiometry Calculating Molar Mass Avogadro’s Number and the Mole Percentage Composition and Empirical Formulas Molecular.

The Mole The Ten Commolements Thou shalt not use 6.02 x 1023 in vain. Thou shalt not use the term mole if thou has no true knowledge of the term mole.

1 Chapter 10 “Chemical Quantities” Yes, you will need a calculator for this chapter!

Chapter 7 Moles. What is a Representative Particle The smallest unit into which a substance can be broken down without changing the composition of the.

Moles and Formula Mass.

Moles and Formula Mass.

Moles and Formula Mass.

The Mole 1 dozen = 12 1 gross = ream = mole = 6.02 x 1023

Stoichiometry “In solving a problem of this sort, the grand thing is to be able to reason backward. This is a very useful accomplishment, and a very easy.

Jonathan Seibert PNHS - Chemistry

Presentation transcript:

AP Chemistry Chapter 3 Chemical Quantities (The Mole)

Amedeo Avogadro Hypothesis: Equal volumes of different gases at the same temperature and pressure contain equal numbers of particles. H2 hydrogen CH4 methane Amadeo Avogadro

The Mole 1 dozen = 12 1 gross = 144 1 ream = 500 1 mole = 6.02 x 1023 There are exactly 12 grams of carbon-12 in one mole of carbon-12.

I didn’t discover it. Its just named after me! Avogadro’s Number 6.02 x 1023 is called “Avogadro’s Number” in honor of the Italian chemist Amedeo Avogadro (1776-1855). I didn’t discover it. Its just named after me! Amadeo Avogadro

The Mole (Quantities) Mass: 1 mole = Molar mass (periodic table) Volume: 1 mole = 22.4 L for a gas @STP Representative Particles: 1 mole = 6.02 x 1023 atoms molecules formula units (elements) (nonmetals) (cation-anion)

1. Convert 3.00 moles of ammonia, NH3, to grams of ammonia.

You have to find molar mass. 1. Convert 3.00 moles of ammonia, NH3, to grams of ammonia. Conversion factor: 1 mole NH3 = ?? g NH3 g NH3 3.00 mol NH3 x = g NH3 mol NH3 You have to find molar mass. (Use Periodic Table)

NH3 Molar mass of ammonia. N H 1 mole NH3 = 17.04 g NH3 14.01 g 1.01 g x 1 x 3 14.01 g + 3.03 g = 17.04 g NH3 1 mole NH3 = 17.04 g NH3

1. Convert 3.00 moles of ammonia, NH3, to grams of ammonia. Conversion factor: 1 mole NH3 = 17.04 g NH3 1 17.04 g NH3 3.00 mol NH3 51.1 g NH3 x = g NH3 mol NH3 NH3 On calculator: 3.00 x 17.04 = 51.12 14.01 1.01 x 1 x 3 14.01 g+ 3.03 g = 17.04 g/mol Round to 3 sig. figs.

Ch. 7 (Calculating Chemical Quantities) 17.04 g NH3 1 mol NH3 1. = 51.1 g NH3 14.01 1.01 x 1 x 3 14.01 g + 3.03 g = 17.04 g/mol 2. 3.

2. How many molecules of carbon dioxide are in 2.00 moles of CO2?

1 mole = 6.02 x 1023 representative particles How many molecules of carbon dioxide are in 2.00 moles of CO2? Conversion factor: 1 mole CO2 = 6.02 x 1023 molecules CO2 molec. CO2 2.00 mol CO2 x = molec. CO2 mol CO2 1 mole = 6.02 x 1023 representative particles CO2 is made of all nonmetals so rep. particles are “molecules”

How many molecules of carbon dioxide are in 2.00 moles of CO2? Conversion factor: 1 1 mole CO2 = 6.02 x 1023 molecules CO2 6.02 x 1023 molec. CO2 2.00 mol CO2 x = 1.20 x 1024 molec. CO2 molec. CO2 mol CO2 On calculator: 2.00 x (6.02 x 1023) = 1.204 x 1024 Round to 3 sig. figs.

Ch. 7 (Calculating Chemical Quantities) 17.04 g NH3 1 mol NH3 1. = 51.1 g NH3 14.01 1.01 x 1 x 3 14.01 g + 3.03 g = 17.04 g/mol 2. 1.20 x 1024 molec. CO2 3.

1 mole = 22.4 L (for any gas @ STP) 3. How many moles of oxygen are in 44.8 L of oxygen, O2? Conversion factor: 1 1 mole O2 = 22.4 L O2 22.4 mol O2 44.8 L O2 x = 2.00 moles O2 moles O2 L O2 On calculator: 44.8 ÷ 22.4 = 2 Show to 3 sig. figs. 1 mole = 22.4 L (for any gas @ STP)

Ch. 7 (Calculating Chemical Quantities) 17.04 g NH3 1 mol NH3 1. = 51.1 g NH3 14.01 1.01 x 1 x 3 14.01 g + 3.03 g = 17.04 g/mol 2. 1.20 x 1024 molec. CO2 3. 2.00 mol O2

24.3 g Li 4. How many grams of lithium are in 3.50 moles of lithium? Conversion factor: 1 1 mole Li = g Li 6.94 g Li 3.50 mol Li x = 24.3 g Li g Li mol Li On calculator: 3.50 x 6.94 = 24.29 Round to 3 sig. figs.

The Mole (Quantities) Mass: 1 mole = Molar mass (periodic table) Volume: 1 mole = 22.4 L for a gas @STP Representative Particles: 1 mole = 6.02 x 1023 atoms molecules formula units (elements) (nonmetals) (cation-anion)

2.62 mol Li 5. How many moles of lithium are in 18.2 grams of lithium? Conversion factor: 1 1 mole Li = g Li 6.94 mol Li 18.2 g Li x = 2.62 mol Li mol Li g Li On calculator: 18.2 ÷ 6.94 = 2.6225 Round to 3 sig. figs.

Representative Particles: Using Avogadro’s Number Use 6.02 x 1023 when looking for atoms, molecules, or formula units 6. How many atoms of lithium are in 3.50 moles of lithium? 6.02 x 1023 atoms Li 3.50 mol Li x = atoms Li 2.11 x 1024 1 mol Li

Representative Particles: Two-part problem 7. How many atoms of lithium are in 18.2 g of lithium? 6.02 x 1023 atoms Li 1 mol Li 18.2 g Li x x 6.94 g Li 1 mol Li (18.2)/6.94 x (6.02 x 1023) = atoms Li 1.58 x 1024

8. A sample of sodium chloride, (NaCl) commonly called table salt contains 7.86 g of sodium and 18.14 g of chlorine. Find the % composition. Find total mass of NaCl 7.86 g + 18.14 g Total mass = 26.00 g Take the mass of the element divided by total mass. 7.86 g %Na = X 100 = 30.23 % Na 26.00 g 18.14 g %Cl = X 100 = 69.77 % Cl 26.00 g

C3H8 C H = = 9. Find the % composition of propane, (C3H8). 12.01 g 6 C 12.01 1 H 1.01 12.01 g 1.01 g x 3 x 8 36.03 g + 8.08 g = 44.11 g C3H8 36.03 g %C = X 100 = 81.68 % C 44.11 g 8.08 g %H = X 100 = 18.32 % H 44.11 g

10. A 12. 8 g sample of a gas contains 6. 4 grams of sulfur and 6 10. A 12.8 g sample of a gas contains 6.4 grams of sulfur and 6.4 grams of oxygen. What is the empirical formula for this gas?

Formulas empirical formula = CH Empirical formula: the lowest whole number ratio of atoms in a compound. Molecular formula: the true number of atoms of each element in the formula of a compound. molecular formula = (empirical formula)n where n = integer molecular formula = C6H6 = (CH)6 empirical formula = CH

Formulas (continued) Formulas for molecular compounds MIGHT be empirical (lowest whole number ratio). Molecular: H2O C6H12O6 C12H22O11 Empirical: H2O CH2O C12H22O11 All can be divided by 6

Empirical Formula Determination Convert grams values to moles for each element. Divide by lowest moles. If necessary: Multiply each number by an integer to obtain all whole numbers.

S O SO2 Empirical Formula S O x x 10. A 12.8 g sample of a gas contains 6.4 grams of sulfur and 6.4 grams of oxygen. What is the empirical formula for this gas? 1. Convert to moles. 16 S 32.07 8 O 16.00 2. Divide by lowest moles. 1 mol S x 6.4 g S = 0.1995 mol S = 0.20 mol S 1 32.07 g S 0.20 mol 1 mol O 6.4 g O x = 0.4 = 0.40 mol O 2 16.00 g O 0.20 mol S O SO2 Empirical Formula

H C O H2CO3 Empirical Formula H C O Assume 100 g sample = 3.16 mol H 11. An unknown clear colorless liquid with no odor is analyzed and found to contain the following. Determine the empirical formula. 3.2 % Hydrogen 19.4% Carbon 77.4% Oxygen = 3.2 g H = 19.4 g C = 77.4 g O 1. Convert to moles. 2. Divide by lowest moles. 1 H 1.01 6 C 12.01 8 O 16.00 Assume 100 g sample 1 mol H 3.2 g H = 3.16 mol H = 3.2 mol H x 2 1.01 g H 1.6 mol 1 mol C 19.4 g C x = 1.62 = 1.6 mol C 1 12.01 g C 1.6 mol 1 mol O 77.4 g O x = 4.84 = 4.8 mol O 3 16.00 g O 1.6 mol H C O H2CO3 Empirical Formula

8. A sample of sodium chloride, (NaCl) commonly called table salt contains 7.86 g of sodium and 18.14 g of chlorine. Find the % composition. NaCl 11 Na 22.99 17 Cl 35.45 22.99 g 35.45 g x 1 x 1 22.99 g + 35.45 g = 58.44 g NaCl 22.99 g %Na = X 100 = 39.34 % Na 58.44 g 35.45 g %O = X 100 = 60.66 % Cl 58.44 g

The Mole (Quantities) Mass: 1 mole = Molar mass (periodic table) Volume: 1 mole = 22.4 L for a gas @STP Representative Particles: 1 mole = 6.02 x 1023 atoms molecules formula units (elements) (nonmetals) (cation-anion)