Hon Chemistry 10-29-13 Empirical & Molecular Formula Practice

HON CHEMISTRY: I was really impressed today with the progress you’ve made on mastering empirical and molecular formulas! Here’s the short review that we did on #52 and the problem from the back of the book.

Are you starting to catch on to the steps? It will be good for you to memorize the steps, but would it not be just tons better to understand why you need each step – backwards and forwards, so then you wouldn’t need to memorize them at all!

Help Session Thursday morning, 7:15ish A.M.

HON CHEMISTRY 10-29-13 Empirical & Molecular Formulas Practice from Tammy Skinner on Vimeo.

flickr photo by Darwin Bell

Physics 10-29-13 Equilibrium Problems Practice

PHYSICS: Great work today thinking through these problems! A couple of things that work for me – draw them first. Then go back through and separate resultants into components. If an object is in equilibrium, then there are no net forces – all the forces in the x direction balance – everything left equals everything right, and all the forces up equal all the forces down.

You’ve got all the ammo you need, now go forth and conquer!

UPDATE: Answers below:

  1. Fn = 3430 N upward against feet
  2. Fn,1 = Fn,2 = 1890 N upward on each foot
  3. Fforward = 4.59 N
  4. FT,1 = FT,2 = 1760 N
  5. FT,1 = 1.36 × 103 N and FT,2 = 680. N

PHYSICS 10-29-13 Equilibrium Problems Practice from Tammy Skinner on Vimeo.

flickr photo by loop_oh

Chemistry 10-29-13 Moles, Mass, Atoms & Avogadro

CHEMISTRY: So… how big a bucket do you think we’d need to hold a mole of frogs? 🙂 Nope, not the furry brown creature that burrows underground, it’s a whole different thing! Here’s the lecture from Tuesday on moles, mass, and Avogadro’s number. I still say he has a cool name…

CHEMISTRY 10-29-13 Moles, Mass & Avogadro from Tammy Skinner on Vimeo.

flickr photo by Thomas Hawk