10.2. Mass, Volume, and the Mole http://www.ck12.org
3 .00 mol CaCl 2 ×^1101 mol CaCl.^98 g CaCl^2
2
=333 g CaCl 2When you measure out 333 g of CaCl 2 , the resulting sample will contain 3.00 moles of CaCl 2.
FIGURE 10.5
Calcium chloride is used as a drying
agent and as a road deicer.Sample Problem 10.4: Converting Moles to Mass
Chromium metal is used for decorative electroplating of car bumpers and other surfaces. Find the mass of 0.560
moles of chromium.
Step 1: List the known quantities and plan the problem.
Known
- 0.560 mol Cr
- molar mass of Cr = 52.00 g/mol
Unknown
- 0.560 mol Cr =? g
The molar mass of chromium will allow us to convert from moles of Cr to grams.
Step 2: Calculate.
0 .560 mol Cr×^521 .mol Cr^00 g Cr= 29 .1 g CrStep 3: Think about your result.
Since the desired amount was slightly more than one half of a mole, the mass should be slightly more than one
half of the molar mass. The answer has three significant figures because the given value (0.560 mol) also has three
significant figures.