Moles Grams

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Moles Grams
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Intro

• Today we will be converting moles to grams, and
  then grams to moles.

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Moles to Grams

• Calculate the mass of 3.00 mol of NaCl.
• 1. Calculate the molar mass of NaCl.
• 2. Convert moles to grams.

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1. Calculate the molar mass of NaCl

• 1. Na (22.990) Cl (35.453) 58.443 g

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2. Convert moles to grams

• 3.00 mol NaCl x 58.443 grams NaCl
• 1 1 mol
  NaCl
• Answer 175.329 grams, rounded to 175 g NaCl

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Convert 9.45 mol of Al2O3 to grams

• 1. Calculate the molar mass of Al2O3

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Convert 9.45 mol of Al2O3 to grams

• 1. Molar mass of Al2O3
• 2 x (26.982) 3 x (15.999) 101.961 grams
• Dont round until the very end!

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Convert 9.45 mol of Al2O3 to grams

• 2. Convert moles to grams
• 9.45 mol Al2O3 x 101.961 grams Al2O3
• 1 1 mol
  Al2O3

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Convert 9.45 mol of Al2O3 to grams

• 2. Convert moles to grams
• 9.45 mol Al2O3 x 101.961 grams Al2O3
• 1 1 mol
  Al2O3
• 963.53145 rounded to 964 grams Al2O3

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Convert 0.452 moles of C20H42 to grams

• 1. Calculate the molar mass of C20H42

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Convert 0.452 moles of C20H42 to grams

• 1. Calculate the molar mass of C20H42
• 20 x (12.011) 42 (1.0079) 282.5518 g

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Convert 0.452 moles of C20H42 to grams

• 2. Convert moles to grams
• 0.452 mol C20H42 x 282.5518 grams C20H42
• 1 1 mol
  C20H42

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Convert 0.452 moles of C20H42 to grams

• 2. Convert moles to grams
• 0.452 mol C20H42 x 282.5518 grams C20H42
• 1 1 mol
  C20H42
• 127.71341 rounded to 128 grams C20H42

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Last practice Convert 2.5 mole of Fe(OH)2

• 1. Calculate molar mass.

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Convert 2.5 mole of Fe(OH)2

• 1. Calculate molar mass.
• 55.845 2 x (15.999) 2 x (1.0079) 89.8588
  grams

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Convert 2.5 moles of Fe(OH)2

• 2. Convert moles to grams
• 2.5 mole Fe(OH)2 x 89.8588 grams
• 1 1 mol Fe(OH)2

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Convert 2.50 moles of Fe(OH)2

• 2. Convert moles to grams
• 2.5 mole Fe(OH)2 x 89.8588 grams
• 1 1 mol
  Fe(OH)2
• 224.647 grams rounded to 220 grams Fe(OH)2
  

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Mass to moles

• 1. Determine the molar mass
• 2. Convert mass to moles

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Convert 92.2 g Fe2O3 to moles

• 1. Calculate the molar mass

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Convert 92.2 g Fe2O3 to moles

• 1. Calculate the molar mass
• 2 x (55.845) 3 x (15.999) 159.687 grams

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Convert 92.2 g Fe2O3 to moles

• 1. Calculate the molar mass
• 2 x (55.845) 3 x (15.999) 159.687 grams
• 2. Convert grams to moles

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Convert 92.2 g Fe2O3 to moles

• 1. Calculate the molar mass
• 2 x (55.845) 3 x (15.999) 159.687 grams
• 2. Convert grams to moles
• 92.2 grams Fe2O3 x 1 mole Fe2O3
• 1 159.687 grams
  Fe2O3

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Convert 92.2 g Fe2O3 to moles

• 1. Calculate the molar mass
• 2 x (55.845) 3 x (15.999) 159.687 grams
• 2. Convert grams to moles
• 92.2 grams Fe2O3 x 1 mole Fe2O3
• 1 159.687 grams
  Fe2O3
• 0.5773748 moles 0.577 moles Fe2O3

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Convert 75.0 g of N2O3 to moles

• 1. Calculate molar mass of N2O3

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Convert 75.0 g of N2O3 to moles

• 1. Calculate molar mass of N2O3
• 2 x (14.007) 3 x (15.999) 76.011 grams
• 2. Convert grams to moles

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Convert 75.0 g of N2O3 to moles

• 1. Calculate molar mass of N2O3
• 2 x (14.007) 3 x (15.999) 76.011 grams
• 2. Convert grams to moles
• 75.0 grams N2O3 x 1 mole N2O3
• 1 76.011 grams N2O3

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Convert 75.0 g of N2O3 to moles

• 1. Calculate molar mass of N2O3
• 2 x (14.007) 3 x (15.999) 76.011 grams
• 2. Convert grams to moles
• 75.0 grams N2O3 x 1 mole N2O3
• 1 76.011 grams N2O3
• 0.9866992 moles N2O3 0.987 moles N2O3

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Convert 45 grams of water to moles

• 1. Calculate molar mass

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Convert 45 grams of water to moles

• 1. Calculate molar mass of H2O
• 2 x (1.0079) 15.999 18.0148 grams
• 2. Convert grams to moles

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Convert 45 grams of water to moles

• 1. Calculate molar mass of H2O
• 2 x (1.0079) 15.999 18.0148 grams
• 2. Convert grams to moles
• 45 grams H2O x 1 mole H2O
• 1 18.0148 grams H2O

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Convert 45 grams of water to moles

• 1. Calculate molar mass of H2O
• 2 x (1.0079) 15.999 18.0148 grams
• 2. Convert grams to moles
• 45 grams H2O x 1 mole H2O
• 1 18.0148 grams H2O
• 2.4979461 moles H2O 2.5 moles H2O

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Agenda

• 1. Read pages 286-299 in the red textbook.
• 2. In your notebooks, answer questions 9-15 on
  page 296.
• 3. Complete the Mole Practice 2 worksheet. Due
  next class.
• Anything you dont finish today is homework.