SOLUTIONS
Solutions are homogeneous mixtures
Solutions are made up of
1)
Vocabulary:
Solute –
2) Solvent Solutions can be classified as
1)
Electrolyte solutions –
2) Nonelectrolyte solutions –
Components that make up mixtures can be
1)
Miscible –
2) Immiscible substances Solids are never completely miscible or immiscible.
There is a limit to the amount of solute that can be dissolved in a given amount of solvent - this is the
"solubility" of the solute.
Solubility of a solute can be expressed in the following qualitative terms:
1)
Soluble –
2) Insoluble –
3)
Slightly soluble -
CONCENTRATION OF SOLUTIONS
The concentration of a solution refers to the amount of solute dissolved in the solvent
Qualitative terms used are dilute (not much solute) and concentrated (alot of solute) - concentrated does not mean pure.
Quantitative measures of concentration:
Molarity (M) - most used other units include: molality, normality, formality , mole fraction, % weight, % volume (proof)
SAMPLE PROBLEM #1
3.85 g of NaCl is dissolved in enough water to make 81.0 mL of soln. Calculate the molarity of the solution.
SAMPLE PROBLEM #2
How many grams of NaCl are required to make 450 mL of .500 M soln?
SAMPLE PROBLEM #3
How many mL of a .250 M NaCl soln can be prepared using 7.51 g NaCl?
SAMPLE PROBLEM #4
25.0 mL of .325 molar hydrochloric acid (HCl) completely neutralizes 35.0 mL of a calcium hydroxide solution. What is the
molarity of the calcium hydroxide solution?
SAMPLE PROBLEM #5
How many mL of .525 M nitric acid (HNO3) solution would completely neutralize 22.5 mL of .275 M Ca(OH)2 base solution?
SAMPLE PROBLEM #6
20.0 mL of .250 M HCl solution is added to 30.0 mL of .150 M HCl solution. What is the concentration of the resulting
solution?
SAMPLE PROBLEM #7
10.0 mL of .375 M HCl solution is diluted by adding water to a new volume of 50.0 mL of solution. What is the concentration
of the resulting solution?
SAMPLE PROBLEM #8
Indicate the concentration of each ion present in the solution formed by mixing 44.0 mL of 0.100 M Na2SO4 and 25.0 mL of
0.150 M KCl.
SAMPLE PROBLEM #9
1.00 g of aluminum reacts with 75.0 mL of 0.300 M ZnI2 solution. How many grams of zinc are produced?
SAMPLE PROBLEM #10
75.0 mL of 0.300 M ZnI2 soln is added to 125 mL of 0.450 M AgNO3 soln. How many grams of the precipitate AgI are
produced?
Due Wednesday:
CHEMISTRY PROBLEMS ON SOLUTIONS
1. How many grams of potassium nitrate are required to make 500 mL of a .250 molar solution?
2. How many grams of sugar, C12H22O11, are required to make 50.0 mL of .800 molar solution?
3. 49.0 grams of sulfuric acid (Hydrogen sulfate) is added to enough water to make 3.00 liters of solution. What is the molarity?
4. What is the molarity of 5.00 liters of solution made with 446 grams of calcium bromide?
5. 7.31 grams of sodium chloride will make how many mL of .500 molar solution?
6. 15.0 mL of .275 molar sulfuric acid solution completely neutralizes 20.0 mL of sodium hydroxide solution. What is the
concentration of the sodium hydroxide solution?
7. 165 mL of .200 molar barium hydroxide solution reacts completely with .750 molar hydrochloric acid solution. What volume
of the acid solution will be required?
8. An excess of zinc metal reacts with 400 mL of hydrochloric acid and releases 2.55 liters of hydrogen gas at STP. What is the
concentration of the acid solution?
9. 10 mL of .400 molar sulfuric acid is added to 25 mL of .200 molar sulfuric acid solution. What is the concentration of the
resulting solution?
10. 100 mL of .375 molar sodium hydroxide solution is diluted with water to a volume of 750 mL. What is the concentration of the
final solution?
11. A solution of sulfuric acid has a volume of 250.0 mL and a concentration of 0.200 M. A 50.0 mL sample of the acid is
withdrawn and added to enough water to make 950.0 mL of a new solution. What is the concentration of the new solution?
12. 30.0 mL of the solution from problem #11 is added to 25.0 mL of 0.0250 M sodium hydroxide solution. What mass of water is
produced in the reaction?
13. What is the concentration of the sodium sulfate solution produced in problem #12?
From Textbook 4(60, 64, 68, 72a, 72c, 74, 86, 113c)