Limited time offer 20% OFF StudySoup Subscription details

# Mason - CHEM 211 - General Chemistry 1 Week 5 - Class Notes

### Created by: Adrien McCulloch Elite Notetaker

> > > > Mason - CHEM 211 - General Chemistry 1 Week 5 - Class Notes

Mason - CHEM 211 - General Chemistry 1 Week 5 - Class Notes

This preview shows pages 1 - 2 of a 3 page document. to view the rest of the content
CHEM 211  MW 10:30-11:45 AM  Prof. Gregory Foster  Page 1 of 3     Notes for Week of 10/2  I.  Solute concentration – Molarity  a.  Molarity = mol of solute / L of solution
b.  Defines the concentration of the solute in the solvent
c.  Calculations
1.  26.8 g of NaCl is added to water forming a 500 mL solution. What  is molar concentration of NaCl  2.  Convert grams of solute to moles
3.  Divide the mole amount by .5 L
ii.  Changing the concentration by diluting to 2 L  1.  M1V1=M2V2  a.  This tells us that the moles of solute will not change, only  the volume does  2.  M2=(M1V1)/V2
3.  Gives us the now molar concentration
iii.  You remove 150 mL and dilute it to 2 L. New concentration of NaCl?  1.  Use the M1V1 equation again
2.  M2=M1V1/V2
3.  Use the new volume that was removed for V1
iv.  What is the concentration of Al3+ in .240 M Al2(SO4)3  1.  .240 M Al2(SO4)3 * 2 mol Al3+/ 1 mol compound = .480 M Al3+  v.  How many total ions in a 500 mL solution .240 M Al2(SO4)3  1.  Molarity * Liters to find moles
2.  Moles * 5 moles of ions/ 1 mol of compound
3.  Moles of ions * avogadros number
II.  Ionic compounds & dissolution  a.  Strong electrolyte = 100% dissociation  a.  NaCl  Na+ + Cl- is a strong electrolyte because it  completely dissolves  b.  Weak electrolyte <100% dissociation  a.  HF  H+ +F- is a very weak electrolyte bc only about 3%  of it dissolves  III.  3 broad categories of chemical reactions  a.  Precipitation Reactions  i.  Ba(NO3)2 (aq)+ Na2SO4(aq)  BaSO4 + 2NaNO3  ii.  If we add two soluble compounds together we typically get a precipitate  iii.  Double displacement   1.  We re-pair the anions and cations with each other  iv.  How do we determine if something forms a precipitate?  1.  Look at the solubility rules in table 4.1
2.  If it doesn’t fall within the first three rules you should consider it
insoluble  v.  Writing equations
CHEM 211  MW 10:30-11:45 AM  Prof. Gregory Foster  Page 2 of 3     1.  Molecular  a.  When we have the compounds always expressed in the  molecular form  b.    2.  Total ionic  a.  Rewrite everything as individual ions unless they are not  dissolved  3.  Net ionic  a.  Remove all the spectator ions  vi.  Calculating how much precipitate formed  1.  First we have to convert moles of solute to moles of ion  a.  We do this by using the molarity of the ion multiplied by  the volume of the solution  2.  Then we do a limiting reactant equation because one of the ionic  quantities will limit how much can be made  b.  Acid-Base reactions  i.  Any compound that releases H+ ions in a solution is an acid  ii.  Compounds that release Oh(hydroxide) is a base  iii.  Acid dissociation and proton transfer  1.  HCl  H+ and Cl-      = strong acid, again strong is determined ny  the amount of dissociation  2.  NaOH  Na+ + OH-  iv.  Strong acids  1.  HCl, HBr, HI, HNO3, H2SO4, HClO4  v.  Strong Base  1.  Group 1 and 2 hydroxides  vi.  Hydronium ion is an example of proton transfer  1.  HCl + H2O  H3O + Cl
2.  Same with
a.  NH3 + H2O  OH + NH4  3.  Acids are proton donors and bases are proton acceptors  vii.  Neutralization reactions. Acid + Base. Form water + salt.  1.  Acid + Base  H2O + Salt  viii.  Weak acid strong base neutralization reactions  1.    c.  Redox reactions  i.  Oxidation + reduction  1.  Oxidation – loss of electrons, always paired with a reduction  reaction  2.  Reduction – gain of electrons  ii.  Oxidizing and reducing agents  1.  Characterized by transfer of electrons as opposed to the previous  reactions which didn’t have any transfer of electrons

This is the end of the preview. Please to view the rest of the content
Join more than 18,000+ college students at George Mason University who use StudySoup to get ahead
##### Description: These notes cover the in class notes from the week of October 2nd
3 Pages 8 Views 6 Unlocks
• Notes, Study Guides, Flashcards + More!
Recommended Documents
Get Full Access to Mason - CHEM 211 - Class Notes - Week 5
×
Get Full Access to Mason - CHEM 211 - Class Notes - Week 5

I don't want to reset my password

Need help? Contact support

Need an Account? Is not associated with an account
We're here to help