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 = representative particles

n 1 mole of eggs would fill all the oceans on Earth…more than 30 million times! A. What is the Mole? n 1 mole of pennies would cover the Earth ¼ mile deep! n 1 mole of basketballs would fill a bag the size of the earth!

B. Mole/Particle Conversions MOLES NUMBER OF PARTICLES N A (particles/mol) Particles = atoms, molecules, formula units, ions, etc N A atoms/mol N A molecules/mol

B. Mole/Particle Conversion Examples n How many molecules are in 2.50 moles of C 12 H 22 O 11 ? 2.50 mol C 12 H 22 O molecules C 12 H 22 O 11 1 mol C 12 H 22 O 11 = molecules C 12 H 22 O 11

n If you have 2.23 x atoms of sodium, how many moles is that? atoms Na 1 mole Na atoms Na 3.70 x moles Na B. Mole/Particle Conversion Examples =

n How many formula units is 3.75 moles of calcium hydroxide? 3.75 mol Ca(OH) formula units Ca(OH) 2 1 mol Ca(OH) 2 = formula units Ca(OH) 2 B. Mole/Particle Conversion Examples

C. Molar Mass n Avogadro discovered the relationship between number of particles and volume of a gas n This was used to find the relationship for particles in a mole

Representative Particles & Moles SubstanceChemical Formula Representative Particle Rep Particles in 1.00 mole Carbon CAtom 6.02 x Nitrogen gas N2N2 Molecule 6.02 x Calcium ion Ca 2+ Ion 6.02 x Magnesium fluoride MgF 2 Formula unit 6.02 x 10 23

C. Molar Mass n Mass of 1 mole of an element or compound n Atomic mass (on the PT) tells the... mass of each atom (amu) grams per mole (g/mol) n Round to 2 decimal places

C. Molar Mass Examples n carbon n aluminum n zinc g/mol g/mol g/mol

C. Molar Mass Examples n water n sodium chloride H 2 O 2(1.01) NaCl = g/mol = g/mol

C. Molar Mass Examples n sodium bicarbonate n sucrose NaHCO (16.00) = g/mol C 12 H 22 O 11 12(12.01) + 22(1.01) + 11(16.00) = g/mol

C. Molar Mass Examples n magnesium hydroxide n ammonium sulfate Mg(OH) (16.00) + 2(1.01) = g/mol (NH 4 ) 2 SO 4 2(14.01) + 8(1.01) (16.00) = g/mol

D. Molar Conversions molar mass (g/mol) MASS IN GRAMS MOLES NUMBER OF PARTICLES N A (particles/mol) Particles = atoms, molecules, formula units, ions, etc N A atoms/mol N A molecules/mol

D. Molar Conversion Examples n How many moles of carbon atoms are in 26 g of carbon? 26 g C 1 mol C g C = 2.2 mol C

D. Molar Conversion Examples n Find the mass of molecules of NaHCO Molecules NaHCO 3 1 mol NaHCO Molecules NaHCO 3 = 290 g NaHCO g NaHCO 3 1 mol NaHCO 3

1 mol K g K D. Molar Conversion Examples n How many moles are in 22.5 grams of potassium? atoms K 1 mol K = 3.46 x atoms K 22.5 g K