Chemistry Homework Assignments and Problems - Due Dates, Reviews, and Exams

Homework 6 posted; due Friday 27 October Finish Reading Chapter 5 Exam 2: Monday 30 October review day is Friday

Harder problems.team efforts with clickers

B1 B1- -Aflatoxin (MW=328.2 g/mol) Aflatoxin (MW=328.2 g/mol) is a naturally occurring, horribly toxic poison is a naturally occurring, horribly toxic poison derived from Aspergillus fungi, a common contaminant in corn. It causes cancer in derived from Aspergillus fungi, a common contaminant in corn. It causes cancer in most humans at the staggeringly low exposure level of 1*10 most humans at the staggeringly low exposure level of 1*1017 the equivalent mass of aflatoxin represented by this count ? the equivalent mass of aflatoxin represented by this count ? ( ( 1 mol count=6.0*10 count=6.0*1023 17 molecules. What is molecules. What is 1 mol 23 .) 58% A. 3.3*10-8 g B. 1.8*10-4 g C. 5.47*10-5g D. 5.06*10-10g E. Not any of above 26% 16% 0% 0% 5.47*10-5g 5.06*10-10g 3.3*10-8 g 1.8*10-4 g Not any of above

Micro chip manufacture requires nearly oxygen Micro chip manufacture requires nearly oxygen- -free conditions wherein the concentration of wherein the concentration of O O2 2 is at or below 17 pg/L. Given that the atomic mass of that the atomic mass of O O is is 16 16 g/mol, g/mol, about how many molecules of molecules of O O2 2 /L /L does this represent ? does this represent ? Note: 1 mol count=6.0*10 count=6.0*1023 free conditions is at or below 17 pg/L. Given about how many Note: 1 mol 23 A. 5.4*1024 B. 3.5*1022 C. 3.2*1011 D. 5.3*1022 94% 6% 0% 0% 5.4*1024 3.5*1022 3.2*1011 5.3*1022

Moles: part 2 Moles: part 2 body body parts parts (mole ratio) math (mole ratio) math: the knee bone is connected to the thigh bone .

How many hands ??? 1 6 5 2 3 4 7 9 8 1 0 11 = 22 hands 2 hands 1 people x 11 people

How many toes connected to the hands (assuming no deformities) ? 5 hands 1 person hand x 5 4 = 50 toes x 10 toes person 3 2 1

Simplest `body parts example 1a : mole Octane = C8H18 How many H are in 20 moles of octane ? Mole 20 mols octane * 18 mol H = 360 mol H mol octane

Isohexane has the formula C6H14. How many C moles are present if we have 0.1667 moles of isohexane ? A. 0.0277 mol C B. 1.00 mol C C. 36 mol C D. 2.333 mol E. None of the above 0% 0% 0% 0% 0% 36 mol C 1.00 mol C 2.333 mol 0.0277 mol C None of the above

Simplest `body parts example 1b: mole Octane = C8H18 How many octane moles contain 24 mol of C? Mole 24 mols C * 1 mol octane = 3 mol C 8 mol C

Vicodin, one of the opiods currently causing an epidemic of drug ODs has the formula: C18H21NO3. How many mol of Vicodin contain 63 mol of H ? 20% 20% 20% 20% 20% A. 0.333 mol B. 1.00 mol C. 2.00 mol D. 3.00 mol E. None of the above 1.00 mol 2.00 mol 3.00 mol 0.333 mol None of the above

`body parts example 2a : Weight moles first, then mol Octane = C8H18 How many moles of octane contain 24 grams of C (at. wt. = 12 g/mol)? Step 1) Convert grams C to moles C (all roads lead through moles divide up) Mol 24 g 12 g/mol C = 2 moles C

`body parts example 2a : (continued) Octane = C8H18 How many moles of octane contain 24 grams of C (at. wt. = 12 g/mol)? Step 2) 2 moles C => how many moles octane? 1 mol octane = x 8 mol C 2 (body parts relationship ?) x= 2/8=0.25 moles octane

Isohexane has the formula C6H14. How many moles of isohexane are formed with 24 grams of C (1 mol C=12 g) A. 0.333 moles isohexane B. 2 moles isohexane C. 0.1667 moles isohexane D. 3 moles isohexane E. Stoichiometry blows F. None of the above 0% 0% 0% 0% 0% 0% 2 moles isohexane 3 moles isohexane 0.333 moles isohexane 0.1667 moles isohexane Stoichiometry blows F. None of the above

`body parts example 2b : Octane = C8H18 How many g of C (at. wt. = 12 g/mol) are in 0.09375 mol of octane ? Step 1) 8 C 1 mol octane 0.09375 (body parts relationship ?) = x x= 8*0.09375=0.75 mol C

`body parts example 2b(cont.)_ : Octane = C8H18 How many g of C (at. wt. = 12 g/mol) are in 0.09375 mol of octane ? Step 2) Multiply down (convert x=0.75 mol C g C) 0.75 mol *12 g/mol =9 grams C

The molecular formula for cocaine is C17H21NO4 and has a molecular mass of 303.4 g/mol. How many grams of O are in 0.03125 mol of cocaine. The atomic mass of O=16 g/mol 25% 25% 25% 25% A. 2.0 g B. 0.50 g C. 9.5 g D. 19.0 g 2.0 g 9.5 g 19.0 g 0.50 g

`body parts example 3a : Weight moles , then mol Octane = C8H18 (MW=114) How many grams of H are in 10 grams of Octane ? (1 mole H=1 g H) Step 1) Convert grams octane to moles octane All roads lead through moles; divide up Mol weight 10 g 114 g/mol = 0.0877 mol octane

`body parts example 3 : Weight moles , then mol Octane = C8H18 (MW=114) How many grams of H are in 10 grams of Octane ? (1 mole H=1 g H) Step 1) Convert grams octane to moles octane All roads lead through moles; divide up Mol weight 10 g 114 g/mol = 0.0877 mol octane

`body parts example 3 (continued) : Octane = C8H18 (MW=114) How many grams of H are in 10 grams of Octane ? (1 mole H=1 g H) Step 2) Relate moles H to moles octane (body parts relationship ?) 14 mol H = x 1 octane 0.0877 x= 14*0.0877=1.228 mol H

`body parts example 3 (continued) : Octane = C8H18 (MW=114) How many grams of H are in 10 grams of Octane ? (1 mole H=1 g H) Step 3) convert moles H to grams H (multiply down) 1.228 mol H * 1 g H/mol=1.228 mol H

Isohexane has the formula C6H14. How many grams of H (at. Wt. = 1 g/mol) are combined in 300 grams of C6H14 (MW=86 g/mol) A. 36.84 g H B. 1.32 g H C. 0.249 g H D. 0.020 g H E. 48.84 g H 91% = x 1 mol octane 0.09375 9% 0% 0% 0% 1.32 g H 36.84 g H 48.84 g H 0.249 g H 0.020 g H

`body parts example 3b : Weight moles , then mol Octane = C8H18 (MW=114) How many grams of octane form from from 2.368 g H? (1 mole H=1 g H) Step 1) Convert grams H to moles H All roads lead through moles; divide up Mol weight 2.368 g H 1 g/mol = 2.368 mol H

`body parts example 3 (continued) : Octane = C8H18 (MW=114) How many grams of octane form from from 2.368 g H? (1 mole H=1 g H) Step 2) Relate moles H to moles octane (body parts relationship ?) 1 mol octane = x 18 mol H 2.368 x= 2.368/18=0.13155 mol octane

`body parts example 3 (continued) : Octane = C8H18 (MW=114) How many grams of octane form from from 2.368 g H? (1 mole H=1 g H) Step 3) convert moles octane to grams octane (multiply down) 0.13155 mol octane*114 g/mol=15 g

Royhypnol or`Roofies, the date rape drug, has the chemical formula C16H12FN3O3 and a molecular mass of 313.3 g/mol. How many grams of Roofie contain 3.676 g of C (atomic mass =12 g/mol) 25% 25% 25% 25% A. 96.97 g B. 22.53 g C. 6.00 g D. 60.0 g 60.0 g 6.00 g 96.97 g 22.53 g

Mole Body Part Calculations level 2: More practice, practice, practice 1)mole to mole: how many moles of O are present in 0.1666 mole of C6 H12O6? 1 mol O 2)mole to mole how many moles of C6H12O6 can be made with 12 mole of O ? 2 moles C6H12O6

Mole Calculations: part 2 (cont.) 3) weight to moles how many moles of C6H12O6 in a sample containing 216 g C ? 3 mol 4)moles to weight how many grams of C6H12O6 are formed with 0.2666 mol H? = 4 g

Mole Calculations: part 2 (cont.) 5) moles to molecules how many molecules of O are present in 0.8333 mol of C6 H12O6? =5*1023 6) molecules to moles how many moles of C6 H12O6 are formed from 4.32*1025 atoms of H ? 6 moles

Mole Calculations: part 2 (cont.) 7) mass to molecules: how many molecules of C6 H12O6 form from 84 g of C ? 7 *1023 molecules ofC6H12O6 8) atoms to mass: how many grams of H are combined with 2.4*1024 atoms of O in C6H12O 6 ? 8 grams H