Chapter 7 Exercise Answers

** 7.11 has been corrected
ODY - Remember that your problem set is due on test day (probably Friday 1/20) and that your work must lead to these answers for credit.  Units must be included. Please slash through units as they cancel. Your work may look different but should lead to the same answer with the same units/sig figs.

Honors - You have begun these exercises. Check the ones you should have completed. We will cover the rest the following week.

7.1 a. 2.0 mol water   d. 2.00 mol carbon dioxide

7.2 a 27 g water         d. 4.04 g molecular hydrogen

7.3 a 67 L Ar             d. 90. L helium

7.4 a 1.25 g/L             d. 0.761 g/L

7.5 44.4 g/mol

7.6 63.8 g/mol

7.7 Ne is twice as fast moving as Kr  (Graham's law is not on this test.)

7.8 a 42.88% C, 57.12% O     b 46.21% Zn, 19.86% Si, 33.93% O    c 3.09% H, 31.60% P, 65.31%O

7.9 45.691% water                           7.10 no calculations just give formula in simplest terms

7.11 a CH₂O     b Ca₃P₂      c Al(ClO₄)₃

7.12 a  CaCl₂     b   CsCl           c Al₂S₃       d Ni(NO₃)₂

7.13 C₆H₆

7.14 C₅H₁₀

7.15 C₄H₁₀

7.16 C₉H₈O₄

Honors Practice Test

Review of Nomenclature Multiple Choice Questions

Honors these are the questions I promised. Odyssey students you could see them as test questions one day as well. Answers are listed if you scroll down far enough.

The essay question requires you to explain nomenclature - make sure you know that molecules generally contain just nonmetals and that we use prefixes to name these. Ex. S02  is sulfur dioxide

Class Notes: Formula Calculations

This powerpoint (click the one titled Formula Calculations) is the one I used in class. You can also find it on the assignment page - click on the paperclip.

Here is another link that explains empirical formula from percentage composition.

The trick to chemistry to practice all the problem solving patterns so here is a link to a powerpoint with more examples. And then a worksheet with 3 questions (and answers!) to practice.

Happy Studying!