Download Key Concepts in Chemistry: Chapter 1 - Ziegler (Fall 04, 9th edition) - Prof. Zelda Ziegle and more Assignments Chemistry in PDF only on Docsity!
CH 221 - Ziegler KEY CONCEPTS Fall 04 Chapter 1 9 th^ edition
Class period 1 – Reading pp. 1-12.
- From its composition, identify a sample of matter as an element, compound, or mixture. Problem 1.7.
- For any element in Table 1.2, given the element name, write the atomic symbol, or vice versa. Problems 1.4, 1.5.
- Classify a mixture as a solution or heterogeneous. Problem 1.2.
- Determine whether a property of matter is a physical or chemical property. Problem 1.14.
Class period 2 – Reading pp. 13(b)-17, 20-24.
- State the appropriate SI/metric unit for a given quantity. Or, given a unit, state the quantity being specified. Problem 1.
- Convert between oF, oC, and K. Problem 1.30.
- Distinguish between precision and accuracy for measured numbers.
- Determine the number of significant figures in a measured quantity. Problem 1.34, 1.36.
- Determine the number of significant figures in a calculated quantity. Problem 1.38,
Class period 3 – Reading pp. 22(b) - 28.
- Use conversion factors to change the units of a measured quantity. Problems 1.44 b), 1.46, 1.
- Relate density to mass and volume. Problems 1.51, 1.63, 1.67 a), b).
CH 221 - Ziegler KEY CONCEPTS Fall 04 Chapter 1 9 th^ edition
Answers to assigned problems:
1.7 See text A-1;
1.4 , 1.5 See table 1.2;
1.2 a) homogeneous mixture, b) heterogeneous mixture, c) pure substance,
d) heterogeneous mixture.
1.14 a) chemical b)physical c) physical d) physical.
1.22 a) volume b) area c) volume d) density e) time f) length e) temperature
1.30 a) 31°C b) 1390 °F c) -140 °F, 178 K d) 297 K, 77 °F e) mp= 24.6 K, bp =27.
K
1.34 140 °C
1.36 a)4 b) 3 c) 4 d) 5 e) 6
1.38 a)1.44 x 10^5 b) 9.75 x 10-2^ c)8.90 x 10^5 d) 6.76 x 10^4 e) 3.40 x 10^4 f) -6.
1.40 -2.3 x 10^3 b) 8.260 x 10^7 c) 3.4 x 10^4 d) 7.62 x 10^5
1.44 b) 1.35 x 10^21 L
1.46 a) 44.39 m b) 539 mL c) 1.35x 10-5^ km/hr d) 3.041 m^3 e) $6.59/kg
f) 0.156 g/mL.
1.54 There are lots of ways to do this. Here’s one way: Select a common unit for comparison,
say, the cm. Then recall that 1 in ~ 2.5 cm, 1 m = 100 cm. Also, it is helpful to notice that 57 cm
is close to 50 cm which is about half as big as the 1.1 m length. 14 in. is about 1.5 times 10 inches
which is easier to convert to cm, (25 cm) so 14 in is around (25 + 12) cm. Sometimes you have to
do the conversions (like when the estimation method isn’t good enough), and sometimes you
don’t (as was the case here). It is useful to make these ball-park estimates so that you can judge
whether your answer is right when you do go through with the more formal conversions.
1.51 See answer in your text.
1.63 peat: 0.13 g/cm^3 ; top soil: 2.5 g/cm^3. No. The densities tell us that a certain volume of
peat moss is “lighter” (weighs less) than the same volume of top soil. Volume must be specified in
order to compare mass.
1.67 a) 4.67 g/cm^3 b) 2.54 L of mercury.
