What are different ways (measurements) or places to buy apples?

Mole Equal toEqual to 6.02 x things (Avogadro’s Number) DefinedDefined to be the number of carbon-12 atoms found in exactly g of carbon-12 DeterminedDetermined through various experiments and calculations in the 20 th century.

Which is more useful for calculating teacher/student ratio There are kg of students in the freshman class There are 190 students in the freshman class The concept of “the mole” allows us to compare quantities of items that have different masses

Like the apple analogy We can quantify chemical substances in 4 different ways … 1.Particles 2.Moles (Number of Particles) 3.Volume 4.Mass We will convert between these 4 ways of quantifying substances

Molar Mass VOLUME MOLE MASS PARTICLES

VOLUME MOLE MASS PARTICLES

C 6 Carbon Atomic Mass: 1 atom of carbon has a mass of amu Molar Mass: 1 mole of carbon (6.02 x atoms) has a mass of g

The Molar Mass is The conversion factor we will use to convert between moles and mass It is the mass (amount of matter) of one mole of a substance We can use the periodic table to help us determine the molar mass

What is the molar mass of titanium? sulfur? chlorine? water? sodium sulfate, Na 2 SO 4 ? calcium nitrate, Ca(NO 3 ) 2 ?

A sample of iron has a mass of 24.5 g. Do we have a mole of iron? How do you know? What mass would a 1 mole sample of sugar, C 12 H 22 O 11, have?

A sample of iron has a mass of 24.5 g. Do we have a mole of iron? How many moles of iron do we have?

Convert g of silver to moles g of sulfur dioxide to moles moles of sodium phosphate to grams Find the molar mass of silver, sulfur dioxide, and sodium phosphate … then

Convert A) 15.6 grams of calcium nitrate, Ca(NO 3 ) 2, to moles B) moles of sulfur dichloride, SCl 2, to grams

Convert A) 10.0 grams of Cu(HCO 3 ) 2 to moles B) moles of Al 2 O 3, to grams

How many things are in a pair? In a dozen? In a mole?

6.02 x VOLUME MOLE MASS PARTICLES

1 mole of any substance contains 6.02x10 23 particles ( Avogadro’s #) 1 mole of carbon contains 6.02x10 23 carbon atoms 1 mole of carbon tetrachloride contains 6.02x10 23 carbon tetrachloride molecules 1 mole of sodium carbonate contains 6.02x10 23 sodium carbonate formula units

1 mole of any substance contains 6.02x10 23 particles ( Avogadro’s #) Atom – Molecule – Formula Unit - Pure element (C, S, Na) Molecular Compound(CCl 4,H 2 O,N 2 ) Ionic Compound (NaCl, Cu 2 S)

Convert 1.59 x oxygen molecules to moles 0.50 moles of potassium to atoms grams of sodium chloride to formula units

Convert 3.0 grams of magnesium chloride to moles 0.34 moles of hexane to molecules 3.4 x10 20 formula units of calcium hydroxide to mass

Do now: What are other words that can be used to describe “particles” in chemistry? Explain how to (step-by-step) convert from a)Moles to particles b)Particles to moles Does the identity of the substance affect how you solve the problem?

22.4 L if a gas at 0ºC and 1 atm(STP) VOLUME MOLE MASS PARTICLES

Try these! What is the volume occupied by 3.00 moles of sulfur dioxide gas, at STP? How many moles of gas are in a balloon whose volume is 1.5 L, at STP?

22.4 L if a gas at 0ºC and 1 atm(STP) (atoms, molecules, formula units) VOLUME MOLE MASS PARTICLES Molar Mass 6.02 x 10 23

Do Now: 1.What are the conversion factors used to convert from mole to a)Mass? b)Particles? (Atoms, Molecules, Formula Units) c)Volume? 2. If the given is in moles, how do you use the conversion factors above? 3. If the answer needs to be found in moles, how do you use the conversion factors above?

Do Now: 1.What is the first step in a mole problem? 2.What is the second step in a mole problem, to help you keep focus? 3.What are the three possible conversions into or out of mole? 4.How do you know if the problem is one step or multistep? 5.Convert … moles of sodium nitrate to mass 4.90 L of nitrogen gas at STP to mole 5.67 grams of Cu to atoms

Try these! A reaction produces g of calcium carbonate. How many formula units of calcium carbonate is this? A 3.0 L balloon holds CO gas at STP. How many molecules of gas are in the balloon. In the transfer of solids, g of copper was left in the beaker. How many atoms of copper is this?

DO NOW! What is the percent composition of this class?

Experimental: Find the percent composition if A) A sample contains 0.16 grams of hydrogen and 2.3 grams of oxygen. B) A sample contains 25.0 g of carbon, 3.9 g of hydrogen, and 30.8 of oxygen.

Theoretical: A)Find the percent composition of water. B)Find the percent composition of glucose, C 6 H 12 O 6 C)How many grams of carbon are there in a 25.0 g sample of glucose.

What is the  Empirical Formula?  Molecular Formula?

 The actual formula for glucose is C 6 H 12 O 6. What is the empirical formula?  What is the empirical formula for water?

Formula Percent Composition Percent Composition Formula

Determine the empirical formula for…  The mineral cassiterite.  Chemical analysis of the mineral cassiterite shows that this compound contains 78.8% tin, by mass, and the rest is oxygen.

 A white powder is analyzed and found to contain g of phosphorus and g of oxygen. What is the empirical formula for this compound?

Do NOw  What is the difference between the empircal and molecular formulas?  Provide the empirical formulas for: H 2 O 2, CaSO 4, C 3 H 6  What steps must you take to find the empirical formula provided with the composition of the compound…either percentages or masses?

1  The compound methyl benzoate, used in the manufacture of perfumes, consists of 70.58% C, 5.93% H and 23.49% O, by mass. Also, by experiment the molar mass is found to be 136 g/mol. What are the empirical and molecular formulas of methyl benzoate?

 What is the empirical formula of a compound that is 66.0% Ca and 34.0% P?