Date In Class Homework 10/22 Thur Counting By Mass Lab 10/23 Fri (mole day!!!) THE MOLE! in room 137 10/26 Mon (LSM) More on the Mole Watch empirical and molecular formula video. 10/27 Tue % Composition & Calculating Empirical Formulas work on problems in the packet (1-7 on page 8) 10/28 Wed. Nomenclature Review Prelab for Hydrated Crystal Lab 10/29 Thurs Hydrated Crystal Lab 10/30 Fri NO SCHOOL! whoo hoo!!! 11/2 Mon Work on Unit Packet work on problems in the packet (8-20 on pages 9) Finish all problems in Unit Packet (21 28 on page 10-11) 11/3 Tues Review for Chapter 10 Test Study for Test 11/4 Wed Chapter 10 Test prelab for Types of Chemical Reactions 11/5 Thur Types of Chemical Reactions 1
Notes for chapter 10: 1. What is a mole? 2. What units can a mole be converted to/from: a. b. c. MOLE/PARTICLE (MOLECULES AND ATOMS) 3. How many molecules are in a mole? 4. When converting from molecules/atoms you 5. When converting from moles to molecules/atoms you Mole/Particle Practice: a. How many moles are in 5.3 x 10 26 atoms of copper? b. How many molecules are there in 3.5 moles of sucrose? 2
MOLE/MASS (GRAMS) 6. Define atomic mass in terms of moles: a. What is the atomic mass of 1 mole of a hydrogen atom? b. What is the atomic mass of 1 mole of an aluminum atom? 7. Define molar mass. 8. Show how you calculate the molar mass of water (H 2 O) 9. When converting from grams to moles you 10. When converting from moles to grams you Mole/Gram Practice: a. How many grams of Iron are in 2.7 moles of Iron? b. How many moles of Zinc are in 15 grams of Zinc? c. How many grams are in 23 moles of CO 2? d. How many moles are in 562 grams of CO 2? e. Calculate the molar mass of ammonium carbonate f. How many grams are in3.5 moles of ammonium carbonate? 3
MOLE/VOLUME (LITERS) 11. What does STP stand for? 12. What is the temperature and pressure at STP? 13. At STP when converting from liters to moles you 14. At STP when converting from moles to liters you Mole/Liter Practice: a. How many liters are present in 10 moles of H 2 at STP? b. How many moles are in 17 L of water vapor? THE MOLE: A BRIGE BETWEEN PARTICLES, GRAMS, AND LITERS 15. List the steps used in calculating how many molecules of H 2 O are present in 10.8 grams? 16. How many liters are present in 6 grams of O 2 gas at STP 4
Video on Empirical and Molecular Formulas: Link: https://www.youtube.com/watch?v=wnrabwvhyky or search Tyler Dewitt Empirical and Molecular Formulas Video title is: Empirical Formula and Molecular Formula Introduction Guided Notes What is a molecular formula? Questions What is an empirical formula? Use ethene (which is really butene.) as an example of a molecular and empirical formula. Write the molecular formula and empirical formula for cyanuric triazide What do you divide by to get the empirical formula for C 5 H 10 O 5? What is the empirical formula for C 5 H 10 O 5? When is the molecular formula the same as the empirical formula? Why can many compounds have the same empirical formula? Show an example of several molecular formulas that come from the same empirical formula. Check your learning Practice. Write the empirical formulas for the following compounds: 1. H 2 O 2 2. H 2 O 3. C 2 H 10 O 4 4. C 5 H 10 O 2 Answers to above 1. HO 2. H 2 O 3. CH 5 O 2 4. C 5 H 10 O 2 5
Percent Composition and Calculating Empirical Formulas: 1. What is a percent composition? 2. Write the equation for calculating % composition? % composition = x100 3. Using the molar mass we calculated for ammonium carbonate from page 3 e, show how to calculate the percent of each element in the compound. a. N b. H c. C d. O 4. Calculate the percentage composition for all the elements in barium nitrate? 5. Write each step for how to calculate the empirical formula of a compound using mass or percent composition. a. Step 1. b. Step 2. c. Step 3. d. Step 4. 6
6. Use the steps in 5. to calculate the empirical formula of a compound that contains 28.4 g copper and 71.6 g bromine? 7. Follow the steps in 5. to calculate the empirical formula of a compound that contains 36.4% Carbon and 63.6% Nitrogen 7
Homework Practice Problems answers on last pages 1. Find the molar mass (g/mole) of: a. Na e. MgI 2 b. C f. AgClO 2 c. O 2 g. Cu(NO 3 ) 2 d. KOH h. Mg 3 (PO 4 ) 2 2. Calculate the mass (grams) of: a. 1.00 mole of CaCl 2 b. 2.0 mol of Al c. 0.50 mol H 2 SO 4 d. 0.10 mole of Na 2 O 3. Calculate moles in: a. 16.0 g of O 2. b. 3.2 g of H 2 O c. 168 g of NaHCO 3 d. 6.25g Al 2 O 3 4. Calculate the number of molecules in: a. 3.0 moles OF ANYTHING b. 32 mol of CH 4 c. 1.4 mol of NH 3 d. 2.5 mol O 2 5. Calculate the number of moles in: a. 1.204 x 10 24 molecules b. 3.5 x 10 24 molecules of HCl c. 6.5 x 10 29 molecules of H 2 SO 4 d. 3.5 x 10 12 molecules of SO 3 6. Calculate the number of moles in: a. 45 L F 2 b. 3.5 L SO 2 c. 78.9 L CO 7. Calculate the volume in liters of: a. 4.50 mol NO 2 b. 8.5 mol CO 2 c. 105 mol CO 8
8. Determine mass in grams of 40.0 moles of sodium carbonate. 9. How many grams are in 0.020 moles of Sn 10. How many liters are in 6.0 mol O 2 11. Calculate moles in 510.0 g of aluminum sulfate. 12. How many moles are in 40.0 g Na 2 CO 3 13. How many moles are in 3.00 L of N 2 Moles are the Bridge between units: 14. Determine the mass in grams of 2.35 molecules of C 12 H 22 O 11 15. How many liters are present in 100g of CO 2 (at STP)? 16. How many sulfur atoms are present in 25.0 grams of H 2 SO 4? 17. How many atoms are in 2.00 grams of carbon? (2 steps) 18. Determine the mass of 50L of CO. 19.(challenge) How many moles of carbon atoms are in 3.00 grams of C 2 H 5 OH? Percent Composition: 20. Determine the percentage composition of each element in the following compounds: a. magnesium iodide, MgI 2 %Mg = % I = b. calcium chlorate, Ca(ClO 3 ) 2 %Ca= %Cl = % O = 9
Empirical vs. Molecular formulas 21. Write the empirical formula for each of the following compounds. (Not all will need to be changed!) a. Na 2 O 2 d. Cu 2 C 2 O 4 b. Li 2 SO 4 e. CaC 4 H 4 O 6 c. Hg 2 F 2 f. C 6 H 6 Calculating Empirical Formulas 22. What is the empirical formula of a compound that contains 1.67 g of Ce and 4.54 g of I? 23. What is the empirical formula of benzoic acid (a food preservative) if it contains 68.8% carbon, 4.95% H, and 26.2% O by mass? 24. Calculate the empirical formula for a compound made up of 63.6% iron and 36.4% sulfur. 25. Calculate the empirical formula of a hydrate that is 48.8% magnesium sulfate and 51.2% water (from lab) 26. Calculate the formula for a hydrate that is 37.07% sodium carbonate and 62.93% water (from lab) 10
Nomenclature Practice: 27. Provide the name for each of the following: a. PbCl 2 g. H 2 CO 3 b. Hg(NO 3 ) 2 h. Sn 3 (PO 4 ) 2 c. AgF i. N 3 Br 7 d. Ca(OH) 2 j. H 2 SO 3 e. HF k. HNO 3 f. S 4 O 6 l. Cu(C 2 H 3 O 2 ) 2 28. Provide the formula for each of the following: a. Iron (III) oxide g. acetic acid b. aluminum iodide h. carbon monosulfide c. Lead (II) sulfate i. phosphoric acid d. mercury (II) nitrate j. chlorous acid e. tin (IV) hydroxide k. hydroselenic acid f. ammonium sulfide l. disulfur noniodide 11
Chemistry Chap. 10 HW- Answers 1. a. 22.99 g b. 12.01 g c. 32.00 g d. 56.11 g e. 278.11 g f. 175.32 g g. 187.56 g h. 262.87 g 2. a. 110.98 g b. 53.96 g c. 49 g d. 6.2 g 3. a..500 mol b..18 mol c. 2.00 mol d..0613 mol 4. a. 1.8 x 10 24 molecules b. 1.9 x 10 25 molecules c. 8.4 x 10 23 molecules d. 1.5 x 10 24 molecules 5. a. 2.000 mol b. 5.8 mol c. 1.1 x 10 6 mol d. 5.8 x 10-12 mol 6. a. 2.0 mol b..17 mol c. 3.52 mol 7. a. 101 L b. 190 L c. 2350 L 8. 40.0 moles Na2CO3 x 106g/1mol = 4240g 9. 2.4 g 10. 134 L 11. 510.0 g aluminum sulfate x 1molH2SO4/342g = 1.5 mol 12. 0.377 mol 13. 0.139 mol 14. 2.35 molecules C12H22O11 6.02 x 1023 molecules x 342g/mol = 1.34 x 10-21 g 15. 100g CO2 44g x 22.4L/mol = 50.9 L 16. 1.5 x 10 23 atoms S 17. 2.00 grams C 12 gc x 6.02 x 10 23 atoms/mol = 1.0 x 10 23 atoms C 18. 50L of CO 22.4L x 28g/mol = 62.5 g CO 19. 3.00 grams C2H5OH 46g x 2C/1 C2H5OH = 0.13 mol C atoms 20. a. %Mg= 24.3 / 278.3 x 100 = 8.7% %I = 254/278.3 x 100 = 91.3% b. Cl = 71/207 x 100 = 34.3% O = 96 / 207 x 100 =46.4% 21. Write the empirical formula for each of the following compounds. (Not all will need to be changed!) a. Na2O2 _NaO d. Cu2C2O4 CuCO2 b. Li2SO4 _ Li2SO4 e. CaC4H4O6 CaC4H4O6 c. Hg2F2 HgF f. C6H6 CH 12
22. What is the empirical formula of a compound that contains 1.67 g of Ce and 4.54 g of I? 1.67g/140= 0.012mol 0.012/0.012 = 1 4.54g/127 = 0.036 mol 0.036/0.012 = 3 CeF3 23. What is the empirical formula of benzoic acid (a food preservative) if it contains 68.8% carbon, 4.95% H, and 26.2% O by mass? 68.8g C/12 = 5.73 mol C 5.73/1.64 = 3.5 x 2 7.0 4.95g H/1 = 4.95 mol H 4.95/1.64 = 3 x 2 6 26.2 g O / 16 = 1.64 mol O 1.64/1.64 = 1 x 2 2 C7H6O2 24. Calculate the empirical formula for a compound made up of 63.6% iron and 36.4% sulfur. 63.6/55.8 = 1.14 FeS 36.4g/32 = 1.14 25. Calculate the empirical formula of a hydrate that is 48.8% magnesium sulfate and 51.2% water 48.8g/120 = 0.405 mol MgSO 4 0.405/0.405 = 1 51.2 g/18 = 2.84 mol H 2 O 2.84/0.045 = 7 MgSO4 7 H2O 26. Calculate the formula for a hydrate that is 37.07% sodium carbonate and 62.93% water 37.07g/106 = 0.356 mole (Na) 2 CO 3 0.356/0.356 1 62.9g / 18 = 3.49 mol H 2 O 3.49 / 0.356 9.8 Na2CO3 * 10 H2O 27. Provide the name for each of the following: a. Lead (II) chloride b. mercury (II) oxide c. silver fluoride d. calcium hydroxide e. hydrofluoric acid f. tetrasulfur hexoxide g. carbonic acid h. tin(ii) phosphate i. trinitrogen heptabromide j. sulfurous acid k. nitric acid l. copper (II) acetate 28. Provide the formula for each of the following: a. Fe2O3 g. HC 2 H 3 O 2 b. Al I 3 h. CS c. PbSO4 i. H 3 PO 4 d. Hg(NO 3 ) 2 j. HClO 2 e. Sn(OH) 4 k. H 2 Se f. (NH 4 ) 2 S l. S 2 I 9 13