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Chapter 11 The Mole. Section 11.1 Please have a highlighter and your periodic table out. Standard 3. 3b-Students know the quantity one mole is set by defining one mole of carbon 12 atoms to have a mass exactly of 12 grams.
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Chapter 11 The Mole Section 11.1 Please have a highlighter and your periodic table out
Standard 3 • 3b-Students know the quantity one mole is set by defining one mole of carbon 12 atoms to have a mass exactly of 12 grams. • 3c- Students know one mole equals 6.02 x1023 particles (atoms or molecules)
Words used for counting: • UnitNumerical ValueExample • Dozen 12 Eggs in a carton • Pair 2 Shoes • Ream 500 Sheets of paper • Gross 144 Pencils in a box • Mole 6.02 x 1023 Particles
Never Changes • 1 dozen is always equal to 12 • 1 mole is always equal to 6.02 ×1023
Avogardro’s number •6.02 ×1023 is also called Avogadro’s number •It was named after this guy: Amedeo Avogadro of Italy
Other names for a particle • The mole is the SI unit used for counting the amount of a substance • 1 mole = 6.02 ×1023particles Particles can be atoms, ions, molecules, formula units, etc.
Multiplying a mole • 0.5 moles = 3.01 ×10 23 • 1 mole = 6.02 ×10 23 • 2 moles = 1.20 ×10 24 • 3 moles = 1.80 ×10 24 • 4 moles = 2.41 ×10 24
How big is a mole • 602, 000, 000,000,000,000,000,000 particles • 602 SEXTILLION!!!!
1 mole=atomic mass of each element • The average atomic mass (on the periodic table) tells you how much one mole of an element weighs (it is also called the molar mass). • –Ex. one mole of oxygen atoms weighs 16.00 grams • –Ex. one mole of potassium atoms weighs 39.10 grams
How did scientist come up with this number? • Carbon-12 has exactly 6 protons and 6 neutrons • So it has an atomic mass of exactly 12.00 Scientists measured out exactly 12 grams of carbon-12 • The sample had 6.02 ×1023atoms of carbon • They set 6.02 ×1023to be one mole (like 12 is one dozen)
Steps for mole caluculations • 1. Start with what is given. • 2. (given) x ------------ • 3. The units that are given are placed in the denominator • 4. Your unknown is placed in the numerator • 5. Multiply the top and divide by the bottom
Example of time • How many minutes are in 120 seconds?
Pg 311 examples • 1. Determine the number of atoms in 3.00 moles(mol) of Zn? • 2. Given 4.00 mole (mol) of AgNO3 determine the number of formula units(FMU).
Pg 311 examples continued… • 3. Calculate the number of molecules in 11.5 mol of H2O. • 4a) 5.75 x 1024 atoms Al how many moles?
On your own in your notes needs to be stamped for points • 4b) 3.75 x1024 molecules CO2 How many moles? • 4c) 3.58 x 1023 Formula units ZnCl2 How many moles? • 4d) 2.50 x1020 atoms Fe. How many moles?
Molar Mass and Mole to gram calculation Standard 3.d- Students know how to determine the molar mass of a molecule from its chemical formula and a table of atomic masses.
Molar Mass • The molar mass of a compound can be calculated solving for the sum of the products of each elements’ mass times the number of atoms present.
Examples • EX: Find the molar mass of the following compounds: • P2O5 • C6H12O6 • Fe2(SO4)3
On your own • EX: Find the molar mass of the following compounds: • N2O3 • KC2H3O2 • Ca3(PO4)2
Moles to Grams • EX: Perform the following conversions: • Convert 5.0 moles of Na to grams • Convert 12.0 moles of He to grams • Convert 213 grams of NF3to moles
On your own • PP: Perform the following conversions: • Convert 6.50 moles of O to grams • Convert 25.0 moles of Fe to grams • Convert 0.40 moles of Ne to grams
Converting from particles to grams and grams to particles Standard 3.d
Particles to grams • EX: Perform the following conversions: • Convert 6.5 x 1024 particles of N to grams. • Convert 2.8 x 1027 particles of Ca to grams. • Convert 5.1 x 1022 particles of K to grams.
Grams to particles • EX: Perform the following conversions: • Convert 300.0 grams of H2CO3 to particles. • Convert 20.0 grams of CuF2 to particles.
PP: Perform the following conversions: • Convert 250.0 grams of Na2CO3 to particles. • Convert 10.0 of CaF2 to particles.