Chemistry 11-28-17 Percent Composition

CHEMISTRY: Great job today… a little bit different lab procedure, huh?!! This lab is answered only on notebook paper – be careful to show correct data and calculations!

BTW – I think you’ll find that percent composition problems are really easy to catch on to. Make sure, though, you can write chemical formulas (I won’t give them to you!) and that you’ve memorized the formulas for acids and those chemical names for common substances so that you’ll have something to find the percent composition of!


flickr photo by Τϊζζ¥

Chemistry 11-15-11 Empirical Formulas

CHEMISTRY: So, would you like to be Greg on CSI? Great start on empirical formulas today. 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. And don’t forget the little step you might have to add to the end. Tomorrow – molecular formulas! 🙂


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Chemistry 11-14-11 Percent Composition

CHEMISTRY: Great job today… although, it was kind of weird watching you chew gum in class! Double check your calculations, sig figs, etc. Remember you are finding the percent of SUGAR in gum, so that means the mass of what goes on top? Lab reports are due Monday.

BTW – I think you’ll find that percent composition problems are really easy to catch on to. Make sure, though, you can write chemical formulas (I won’t give them to you!) and that you’ve memorized the formulas for acids and those common substances from #58, so that you’ll have something to find the percent composition of. Don’t stop practicing those as well!


flickr photo by Τϊζζ¥

Hon Chemistry 10-21-11 Percent Composition

HON CHEMISTRY: Great job today… although, it was really weird watching you chew gum in class! I think you’ll find that percent composition problems are super easy to catch on to. Make sure, though, you can write chemical formulas (I won’t give them to you!) and that you’ve memorized the formulas for acids and those common substances from #58. Then, it’s just plug and play from there! 🙂


flickr photo by Τϊζζ¥