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CHAPTER 4: REACTIONS IN AQUEOUS SOLUTIONS 
 
89
 
 (c) 1 mol NaCl? mol NaCl 9.00 g NaCl 0.154 mol NaCl
58.44 g NaCl
= × = 
 
 3
mol solute 0.154 mol NaCl
L of soln 86.4 10 L soln−
= = =
×
Molarity 1.78 M 
 
4.64 (a) 3
3 3 3
3
1 mol CH OH
? mol CH OH 6.57 g CH OH 0.205 mol CH OH
32.042 g CH OH
= × = 
 
 30.205 mol CH OH
0.150 L
= = 1.37M M 
 
 (b) 2
2 2 2
2
1 mol CaCl
? mol CaCl 10.4 g CaCl 0.09371 mol CaCl
110.98 g CaCl
= × = 
 
 20.09371 mol CaCl
0.220 L
= = 0.426M M 
 
 (c) 10 8
10 8 10 8 10 8
10 8
1 mol C H
? mol C H 7.82 g C H 0.06102 mol C H
128.16 g C H
= × = 
 
 10 80.06102 mol C H
0.0852 L
= = 0.716M M 
 
4.65 First, calculate the moles of each solute. Then, you can calculate the volume (in L) from the molarity and the 
number of moles of solute. 
 
 (a) 1 mol NaCl? mol NaCl 2.14 g NaCl 0.03662 mol NaCl
58.44 g NaCl
= × = 
 
 mol solute 0.03662 mol NaClL soln 0.136 L
Molarity 0.270 mol/L
= = = = 136 mL soln 
 
 (b) 2 5
2 5 2 5 2 5
2 5
1 mol C H OH
? mol C H OH 4.30 g C H OH 0.09334 mol C H OH
46.068 g C H OH
= × = 
 
 2 50.09334 mol C H OHmol soluteL soln 0.0622 L
Molarity 1.50 mol/L
= = = = 62.2 mL soln 
 
 (c) 3
3 3 3
3
1 mol CH COOH
? mol CH COOH 0.85 g CH COOH 0.0142 mol CH COOH
60.052 g CH COOH
= × = 
 
 30.0142 mol CH COOHmol soluteL soln 0.047 L
Molarity 0.30 mol/L
= = = = 47 mL soln 
 
4.66 A 250 mL sample of 0.100 M solution contains 0.0250 mol of solute (mol = M × L). The computation in 
each case is the same: 
 
 (a) 259.8 g CsI0.0250 mol CsI
1 mol CsI
× = 6.50 g CsI