Chemistry 11-6-18 Binary Molecular Formulas

CHEMISTRY: Do you feel like you have letter and numbers swimming in your eyes? This is one of those times that paying attention to details is super, super important! Here’s the lecture from today on writing formulas and names for binary molecular compounds. Part of it’s really similar to what you learned to do last week for ionic compounds, but another part is totally different. Details!!

Make sure you keep everything straight. Do something that will organize all the information for you, so you won’t get confused. Also, don’t forget the lists you have to memorize – it’s getting larger and larger!! And practice, practice, practice!!!

Need extra practice? Another help session??


flickr photo by Roger Smith

Hon Chemistry 11-6-18 Empirical & Molecular Formulas

HON CHEMISTRY: Awesome job today!! You just about figured out how to find empirical formulas and molecular formulas all by yourself! I love the way you were able to think through what you knew and what you needed to find a solution!

Be sure and practice – if you don’t it’ll get all turned around and you’ll end up leaving off an important step. The hardest part is that it’s not a set formula for you to plug and play, but if you’ll keep in mind that you’re really just looking for subscripts which are just moles, you’ll be able to think it through. Percent to mass, mass to moles, moles to smallest whole number ratio.

Are you starting to catch on to the steps? It will be good for you to memorize them, 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!

And then, also remember what molecular formulas are – just a multiple of the empirical formula. Keep that concept in mind, and you’ll have no problem remembering to divide the molecular formula mass by the empirical formula mass to find X! Easy peasy! πŸ™‚


flickr photo by Darwin Bell

Physics 11-6-18 Friction Problems & Friction on Inclines

PHYSICS: Who knew snow skiing could be so complicated! Well…friction problems on an incline anyway. Here’s our discussion of friction problems on an incline.

Back to the problems – remember, drawing the diagram is super, super important. Label all the forces and apply the concepts you know about net forces and resultant forces – let it tell you a story. πŸ™‚

Here is some info you might find helpful:
Wed night answers


flickr photo by t i g