Chapter 5 Notes
Popular in General Chemistry
Popular in Department
This 5 page Class Notes was uploaded by Candace Brooks on Friday February 27, 2015. The Class Notes belongs to CH 101 at University of Alabama - Tuscaloosa taught by Paul Rupar in Spring2015. Since its upload, it has received 129 views.
Reviews for Chapter 5 Notes
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 02/27/15
Chapter 5 Naming Molecular Compounds How to Name a Molecular Compound 0 Prefix9Name of the 1539 element9Prefix9Base Name of 2nd element ide Note that these are molecular compounds with covalent bonds The ide does not imply an anion in this case If the first prefix is quotmonoquot it is usually omitted Prefixes o Mono Di Tri Tetra Penta Hexa Hepta Octa Nona Deca Naming Examples 0 PC13 Phosphorus Trichloride o PC15 Phosphorus Pentachloride 0 N20 Dinitrogen Monoxide 0 N02 Nitrogen Dioxide Homummeri x 0 Chapter 5 Molar Mass of compounds Percent Contribution and Chemical Formula Determination What is a Mole o 602x1023 The Molar Mass of a compound is equal to the sums of the atomic masses of its constituent elements 0 Molar Mass of atoms of 15 elements in formula times atomic mass in 15 elements of atoms in 2nd element times atomic mass of 2nd element Converting between Mass Moles and Molar Mass 0 Mass of moles x Molar Mass I Mn x mm n Mmm mmMn I Ex What is the mass of 25 mol of NaCl 0 mm5844gmol 25 mol x 5844 gmol 1461g 15x102g 1513 clicker calculate the molar mass of CH4 0 16gmol 0 How many formula units are there in 8766g of NaCl 0 8766g x 1mol5844 I More Practice 0 How many moles of 0 is present in 32g of H20 I mmH20 quot9 1802 gmol mol of H20 32g x 1 mol1802g 1778 mol 18 mol of 0 0 2nd Clicker How many moles in 453 g of A12SO43 o 0132 mol 0 Chemical Formula 0 The Empirical Formula gives the relative number of atoms I Think of it as the atom ratio 0 The Molecular Formula gives the actual number of atoms 0 Examples Common Name Molecular Empirical Formula Formula Glucose C6H1206 CH20 Carbon Dioxide C02 C02 Hydrogen H202 H0 Peroxide Water H20 H20 Percent Composition 0 Chemical formulas give the element ration in a compound 39 Eg C6H1206 I Ratio of 1C 2H 10 0 However each atom has a different atomic mass Therefore the mass ratio of the elements is different from the atom ratio How to Calculate the Percent Composition 0 Percentage part whole X 100 0 Mass element mass of element x in 1 mol mass of 1 mol compound I Find C by Mass in C02 0 Mass C mass of C in 1 mol of C02 mass of 1 mol of C02 I 1mm ofC02 mm ofo2 mm of0 1201 gmolx 21600 gmol 4401 gmol I 2 M of C02 1 mol x 4401 gmol4401g I 3 M of C 1 mol x 1201 gmol 1201 g I 41201 g4401gx 100 2729 Burning Stuff Gives Us the Percentage Composition 0 Chemists are able to very precisely measure the gases generated when something is combusted Calculating Empirical Formula 0 0 Convert the percentages to grams I a assume you start with 100g of the compound Convert grams to moles Write the pseudoformula using moles as subscripts Divide all by the smallest number of moles I If the result is within 01 of whole number round to whole number Multiply all mole ratios by number to make all whole numbers I If ratio5 multiply all by 2 if ratio33 or 67 multiply all by 3 if ratio 025 or 075 multiply all by 4 etc I Skip if already whole numbers
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'