Transcript Slide 1

Hydrogen bonding…
(a) occurs only between water molecules
(b) is stronger than covalent bonding
(c) can occur between NH3 and H2O
(d) results from strong attractive forces in
ionic compounds
Which of the following is not a general property of
solutions?
(a) a homogeneous mixture of two or more
substances
(b) variable composition
(c) dissolved solute breaks down to
individual molecules
(d) the same chemical composition, the
same chemical properties, and the same
physical properties in every part
Which procedure is most likely to increase
the solubility of most solids in liquids?
(a) stirring
(b) pulverizing the solid
(c) heating the solution
(d) increasing the pressure
The addition of a crystal of NaClO3 to a
solution of NaClO3 causes additional crystals
to precipitate. The original solution was
(a) unsaturated
(b) dilute
(c) saturated
(d) supersaturated
If NaCl is soluble in water to the extent of
36.0 g NaCl / 100 g H2O at 20 oC, then a
solution at 20 oC containing
45.0 g NaCl / 150 g H2O would be…
45.0 g NaCl = X g NaCl
150 g H2O
100 g H2O
X = 30.0 g NaCl is unsaturated
If 5.00 g NaCl is dissolved in 25.0 g H2O,
the percent NaCl by mass is
5.00 g NaCl
5.00 g NaCl + 25.0 g H2O
=
= 16.7 %
5.00
30.0
How many grams of 9.0% AgNO3 solution
will contain 5.3 g AgNO3?
9.0
100
= 5.3
X
X
=
59
What mass of BaCl2 will be required to
prepare 200. mL of 0.150 M solution?
0.150 mol x 0.200 L = 0.0300 mol
L
x 208.3g/mol
= 6.25 g BaCl2
How many grams of a solution that is 12.5 %
by mass AgNO3 would contain 0.400 mol of
AgNO3?
0.400 mol x 169.9 g = 68.0 g AgNO3
mol
12.5 = 68.0 g AgNO3
100
X
X = 544 g of solution
How much solute is present in 250. g of
5.0% K2CrO4 solution?
5.0
100
=
X
250. g solution
X = 12.5 g K2CrO4
First find moles of each reactant
molarity = moles
liters
molarity x liters = moles
0.642 mol x 0.0805 L = 0.0517 mol Ba(NO3)2
L
0.743 mol x 0.0445 L = 0.0331 mol KOH
L
0.0517 mol 0.0331 mol
1 Ba(NO3)2 + 2 KOH → 1 Ba(OH)2 + 2 KNO3
0.0517 mol 0.0331 mol
1 Ba(NO3)2 + 2 KOH → 1 Ba(OH)2 + 2 KNO3
1 Ba(NO3)2 = 0.0517
1 Ba(OH)2
x
= 0.0517 mol Ba(OH)2
2 KOH = 0.0331 mol
1 Ba(OH)2
x
= 0.0166 mol Ba(OH)2
--limiting reactant = KOH
0.0166 mol Ba(OH)2 x 171.3g = 2.84g Ba(OH)2
1 mol