Golden West College CHEM 180

Suggested Homework 2

1. Perform the following calculations, rounding off the answer to the correct number of

significant figures.

(a) 504.2 + 12.8 + 760 = ____________

(b) 504.2 + 12.8 + 760. = ____________

(c) 504.2 + 12.8 + 760.0 = ____________

(d) 945.26 + 290 0.5 = ____________

(e) (8.12103) (4.57104) + (1.53105) = ____________

(f) 8.291 3.70 = _______________

(g) 18.29 58.3 = _______________

(3.722107)(7.106110

6)

(h) -------------------------------- = _______________ (5.210

3)(2.3810

2)

Golden West College CHEM 180

2. Why must units be included with every reported measurement?

3. Perform the following conversions. Report answers to the correct number of significant figures.

(a) 843 cL to liters

(b) 0.02391 kg to grams

(c) 7.10105 m to decimeters

(d) 2820 ns to milliseconds

(e) 7902 lb to ounces

(f) 86.0 ton to ounces

(g) 1.00 year to seconds

Golden West College CHEM 180

(h) 4.5105 qt to centiliters

(i) 43.8 Mg to pounds

(j) 360 F to Celsius

(k) 38.9 C to Fahrenheit

(l) -239.95 C to Kelvin

(m) 8.73 K to Celsius

(n) 341 oF to Kelvin

(o) 309.0 K to Fahrenheit

Golden West College CHEM 180

4. A gas of unknown identity has a mass of 0.1394 g and occupies a volume 850. mL. Use the table of densities in the lecture slides to identify the gas.

5. Mercury has a density of 13.6 g/mL. What is the mass of a 0.24 L sample of mercury?

6. If the density of butter is 0.86 g/mL, what volume is occupied by 427 g of butter?