CHEM 1211L – Lab Begins Next WeekWithdrawal PolicyWithdrawal PolicySlide 4Slide 5Slide 6Slide 7Slide 8Slide 9Slide 10Slide 11Slide 12Slide 13Q2Slide 15Slide 16Slide 17Slide 18Slide 19Slide 20Slide 21•Dress Code–Safety Goggles or Glasses must be worn at all times(Z87 or Z87.1)•No food or drink is permitted in the lab room.•You must complete the Safety Quiz and Prelab Questions for Exp 1.CHEM 1211L – Lab Begins Next WeekStudents who choose to withdraw from lecture (CHEM 1211) before Monday, October 17th, must withdraw from the lab (CHEM 1211L). Students who choose to withdraw from lecture between Monday, October 17th, and the Withdrawal Deadline (Thursday, October 20th) may choose to remain in the lab IF they are passing the lab. Withdrawal PolicyStudents that withdraw from CHEM 1211 prior to 5:00 PM on Thursday, October 20th will receive WP's regardless of their present grade in CHEM 1211. Withdrawal PolicyCh. 2 end of book HW questions: 12, 13, 15-18, 22, 23, 28, 32, 34-36, 38, 40, 42, 44, 45, 49, 50, 53, 54, 56, 60, 62, 66-68, 70-72, 76, 78, 80, 82, 86, 87, 89, 91, 93, 96, 105, 106, 114Buy individual lab experiments: cengagebrain.comNeed same lab manual for 1212Review of nomenclatureCopper (II) bromide CuBr2Potassium nitrate K(NO3)Ammonium sulfate (NH4)2SO4Copper (I) sulfide Cu2SMgO Magnesium OxideCO2 Carbon DioxideAgCl Silver ChlorideCH3CH2CH3 PropaneNH3 Ammonia Benzene C6H6Atomic weights (atomic mass)Atomic mass unit (amu): defined as exactly 1/12 of the mass of an atom of a particular kind of carbon atom, called carbon-12Periodic table has amu.The MoleDefined as the amount of substance that contains as many entities (formula units, ions, atoms, molecules, or other particles) as there are atoms in exactly 0.012 kg of pure carbon-12 atoms.1 mole = 6.022 x 1023 particles (formula units)Avogadro’s numberMole derived from the Latin word moles which means “a mass”. “molecule” is the diminutive form of this word and means a small mass.1 mole of X atoms = atomic mass of X element2 moles of O2 is how many grams?1 mole of H2 = 2.00 g/mol H21 mole of O2 = 32.00 g/mol 022 mole O2 x 32.00 g/mol = 64.00 g of O21 mole of He = 4.00 g = 6.022 x 1023 atoms of He1 mole of H2 = 6.022 x 10 23 molecules of H2= 2 (6.022 x 1023) atoms of H2= 1.20 x 1024 H atomsQ11.23 moles of Ca is how many g?1.23 moles of Ca = 1.23 (40.08) = 49.3 g/mol of CaHow many atoms are contained in 1.245 moles of Na?1.245 moles (6.022 x 1023) = 7.497 x 10 23Formula weights, molecular weights, and molesThe formula weight of a substance is the sum of the atomic weights of the elements in the formula, each taken the number of times the element occurs.Formula weight used for either ionic or molecular substances.Molecular weight used for non-ionic substances.Write the formula for ammonium hydroxide.NH4OHWhat is its formula weight?1 x N = 14.0g/mol5 x H = 5.00 g/mol1 x 0 = 16.00 g/mol= 35.0 g/molHow many g are in 2.5 moles? How many N atoms are there?35.0 g/mol (2.5 moles) = 88 g2.5 moles NH4OH (6.022 x 10 23 formula unit/mole) (1 N/1 formula unit) = 1.5 x 1024 atoms of NWrite the formula for aluminum sulfate. Al2(SO4)3What is its formula weight?2 x Al = 53.96 g/mol of Al3 x S = 96.21 g/mol of S12 x O = 192.00 g/mol of O342.17 g/mol of Al2(SO4)3How many g are in 1.2 moles? How many atoms of Al are there? O atoms?1.2 mol (342.17 g/mol of Al2(SO4)3) = 4.1 x 102 g 1.2 moles Al2(SO4)3 (6.022 x 10 23 formula unit/mole) (2 Al/1 formula unit) = 1.4 x 1024 atoms of Al1.2 moles Al2(SO4)3 (6.022 x 10 23 formula unit/mole) (12 O/1 formula unit) = 8.7 x 1024 atoms of oQ2Write the formula for Fe(III) phosphate.What is its formula weight? Enter that into clicker.How many moles are in 50.0 g of sodium hydroxide?Percent composition and formulas of compoundsPercent composition of waterDerivation of formulas from elemental compositionEmpirical (simplest) formula: is the smallest whole-number ratio of atoms presentExample: benzene (molecular formula C6H6), so empirical formula is ?Molecular formula indicates the actual numbers of atoms present in a molecule of the compoundCalculate the % composition of potassium sulfate.So 44.9% of K and 18.4% of S and 36.7% of O adds up to 100%, then assume you have 100 g of the compound; calculate the number of moles of each element in the formula (so % becomes g), then divide the moles by the lowest number (in moles), should get whole numbers and that’s how you calculate the empirical formulaThe analysis of a salt shows that it contains 56.58% potassium; 8.68% carbon; and 34.78% oxygen. Calculate the empirical formula for this substance.63.6% N, 36.4% O calculate the empirical