Friday March 6 Objective: Determine the ratio of water molecules to copper sulfate molecules in a blue chemical. Checkpoint: How many moles in 3.54 grams of CO2? How many grams in 0.231 moles of CO2? How many molecules in 0.123 grams of H2? How much does 3.24 x 1024 molecules of O2 weigh (in grams)? Homework: Study for quiz on Monday

1 mole CO2 = 44.01 g How many moles in 3.54 grams of CO2? 3.54 g 1 mol 0.080 mol x = 44.01 g

g 1 mole CO2 = 44.01 g 44.01 x = 1 mol 10.167 grams 10.2 grams How many grams in 0.231 moles of CO2? 0.231 mol 44.01 g 10.167 grams 10.2 grams x = 1 mol

Grams  Moles  Molecules How many molecules in 0.123 grams of H2? 0.123 g 1 mol 6.02 x 1023 molecules x x 2.02 g 1 mol 3.6656 x 1022 molecules 3.67 x 1022 molecules

Grams  Moles  Molecules How much does 3.24 x 1024 molecules of O2 weigh (in grams)? 3.24 x 1024 molec 1 mol 32.00 g x x molec 6.02 x 1023 1 mol 172.226 grams 172 grams

Turn in Lab Report (with rubric) now 5 days late

Finding Moles Mini-Lab (due Tuesday)

Mass of test tube + copper sulfate (before heating) Mass of empty test tube Mass of test tube + copper sulfate (before heating) Mass of test tube + copper sulfate (Trial 1) Mass of test tube + copper sulfate (Trial 2) Mass of test tube + copper sulfate (Trial 3) 10.00 grams 20.00 grams 18.00 grams 16.00 grams 15.00 grams

Take out mole worksheet to be stamped Calculate the original mass of hydrated copper sulfate (CuSO4 bonded to water molecules), before heating. Calculate the mass of total water loss in this experiment. Calculate how many moles of water this represents. Calculate the mass of anhydrated CuSO4 (CuSO4 with water burned off), used in this experiment. Calculate how many of moles of CuSO4 this represents. What is the mole ratio of H2O to CuSO4? (moles H2O : moles CuSO4). Round to nearest whole number. 2 - 1 20.00 – 10.00 = 10.00 g CuSO4 2 - 5 20.00 – 15.00 = 5.00 g H2O 5.00 g H2O  moles H2O 5 - 1 15.00 – 10.00 = 5.00 g CuSO4 5.00 g CuSO4  moles CuSO4

3 H2O : 1 CuSO4 26.27 moles of H2O 8.34 moles of CuSO4 What is the mole ratio of H2O to CuSO4? (moles H2O : moles CuSO4). Round to nearest whole number. 26.27 moles of H2O 8.34 moles of CuSO4 26.27 / 8.34 = 3.15 3 H2O : 1 CuSO4

Quiz on Monday Who cares? Why is this useful? moles  grams and grams  moles moles  molecules and molecules  moles grams  moles  molecules molecules  moles  grams Who cares? Why is this useful?

Sugar + 5 Water + Baking Soda + 2 Corn Syrup + 2 Butter + 2 peanuts Sugar + 5 Water + Baking Soda + 2 Corn Syrup + 2 Butter + 2 peanuts  Peanut Brittle Wed / Thurs Please bring $1 to help with materials

Sugar + 5 Water + Baking Soda + 2 Corn Syrup + 2 Butter + 2 peanuts  Peanut Brittle .606 mol get here 0.0161 mol 3.12 mol Start here