Answer:
CHAPTER 17
PROPERTIES OF SOLUTIONS
Solution Composition
12. Mass percent: the percent by mass of the solute in the solution.
Mole fraction: the ratio of the number of moles of a given component to the total number of
moles of solution.
Molarity: the number of moles of solute per liter of solution.
Molality: the number of moles of solute per kilogram of solvent.
Volume is temperature-dependent, whereas mass and the number of moles are not. Only
molarity has a volume term, so only molarity is temperature-dependent.
13. a. HNO3(l) → H+
(aq) + NO3
−
(aq) b. Na2SO4(s) → 2 Na+
(aq) + SO4
2−
(aq)
c. Al(NO3)3(s) → Al3+(aq) + 3 NO3
−
(aq) d. SrBr2(s) → Sr2+(aq) + 2 Br−
(aq)
e. KClO4(s) → K+
(aq) + ClO4
−
(aq) f. NH4Br(s) → NH4
+
(aq) + Br−
(aq)
g. NH4NO3(s) → NH4
+
(aq) + NO3
−
(aq) h. CuSO4(s) → Cu2+(aq) + SO4
2−
(aq)
i. NaOH(s) → Na+
(aq) + OH−
(aq)
14. Mol Na2CO3 = 0.0700 L ×
L
3.0 mol Na 2CO3 = 0.21 mol Na2CO3
Na2CO3(s) → 2 Na+
(aq) + CO3
2−
(aq); mol Na+
= 2(0.21) = 0.42 mol
Mol NaHCO3 = 0.0300 L ×
L
1.0 mol NaHCO3 = 0.030 mol NaHCO3
NaHCO3(s) → Na+
(aq) + HCO3
−