definitions solubilitylabpotpourrisolutions 100 200 300 400 500
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Definitions Solubility Lab Potpourri Solutions
100100 100 100 100100 100
200 200 200 200200 200
300 300 300300 300 300
400 400 400 400 400
500 500 500500 500 500500
100 Definitions
A homogeneous mixture of substances in a single phase
Answer
Definitions 100
Answer = solution
200 Definitions
A solution in which the amount of solute present is less than the
maximum possible at that temperature
Answer
Definitions 200
Answer = unsaturated solution
300 Definitions
molarity
Answer
Definitions 300
Moles of solute per liter of solution
400 Definitions
The word “dissolution” meansAnswer
Definitions 400
dissolving
500 Definitions
Describe the structure of a surfactant and how it works.
Give an example of a surfactant.
Answer
Definitions 500 Answer
• A surfactant is a large molecule with one polar end and one nonpolar end.
• It enables mixing of immiscible substances.
• Shampoo is a surfactant.
100 Solubility
What is meant by the phrase “like dissolves like”?
Answer
Solubility 100 Answer
• Substances of similar polarity are miscible.
• Polar dissolves polar.
• Nonpolar dissolves nonpolar.
200 Solubility
Explain the equilibrium that exists in a saturated solution
Answer
Solubility 200
Answer:
solute particles are dissolving and recrystallizing at equal rates
300 Solubility
Explain how you would use a crystal of solute to determine whether the solution of that solute is saturated,
supersaturated or unsaturated.
Answer
Solubility 300
Answer:A crystal added to the solution will:– dissolve in an unsaturated solution– sink to the bottom in a saturated solution– cause recrystallization to occur in a
supersaturated solution
400 Solubility What units are generally used to indicate solubility of a substance
in water?
Answer
Solubility 400
Answer:
g of solute/100 g water
500 Solubility
Describe the trends in gas solubility as:
a). Pressure increases
b). Temperature increases
Answer
Solubility 500
Answer:
As pressure of the gas above the liquid increases, solubility of the gas in the liquid increases.
As temperature of the liquid increases, solubility of the gas in the liquid decreases.
100 Lab
What solvent will dissolve both polar and nonpolar substances?
Answer
Answer 100 Lab
• Ethanol, because it has a polar OH end and a nonpolar hydrocarbon end.
200 Lab
What is the rapid escape of a gas from a liquid in which it was
dissolved?
Answer
200 Lab Answer
• Effervescence
300 Lab
An aqueous sample of Fe2+ would show what series of colors when
mixed with reagentsK3FeCN6 K4FeCN6 KSCN
Answer
Answer 300 Lab
Fe2+ (aq) plus
K3FeCN6 K4FeCN6 KSCN
Deep blue light blue peach
400 Lab
What mass of NaCl (MM = 58.44 g/mol) is needed to make 75.0 mL of 2.00M
solution?
Answer
Lab 400
Mole= M x L
= 2.00 M x 0.0750 L = 0.15000 mol
g = 0.1500 mol x 58.44 g = 8.77g NaCl mol
500 Lab
Describe at least 3 safety precautions to follow when diluting a strong acid.
Answer
Lab 500
Answer:
Wear gloves, goggles, apron or lab coat.
Do it under the fume hood, fan on.
Always add acid to water.
100 Potpourri
Designate each of the following as an acid or a base:
H3PO4 NH3 LiOH HBr Answer
100 Potpourri
• Answer:
H3PO4 NH3 LiOHHBr
Acid Base BaseAcid
200 Potpourri
What are the three types of solute particles?
Answer
200 Potpourri
• Atoms, ions, molecules
300 Potpourri
Substance A dissolves in water.Substance B dissolves in oil.
Substances A and B are immiscible.Make a generalization about the
polarities of substance A and substance B.
Explain! Answer
300 Potpourri
• Since H2O is polar, substance A must be polar.
• Since A and B are immiscible, as are oil and water, B must be nonpolar.
400 Potpourri
Name the most accurate pieces of glassware for:A. making a solution of a specific volumeB. measuring a small volume of solution which will be diluted.
Answer
400 Potpourri Answer
• A. Volumetric flask
• B. Pipet
Answer
The solubility of ammonia, NH3, is 90 g/100 g of water at 0oC. Draw the solubility curve for this substance.
Answer Potpourri 500
100 Solutions
Give an example of a solution in which the solvent is a solid.
Answer
Answer 100 Solutions
• Alloys such as brass, bronze, sterling silver, white gold are all solid solutions.
200 Solutions
What volume of 2.00 M NaOH contains 10.0 g of solute?
(MM of NaOH = 40.00 g/mol)
Answer
Answer for Solutions 200
Moles = 10.00 g X 1mole = 0.250mole 40.00 g
L = moles = 0.250 mole = 0.125 L Molarity 2.00 M
300 Solutions
What volume of 6.0M HCl is needed to make 3.00 L of
0.500M HCl?Answer in mL.
Answer
Solutions 300
Answer:
MCVC = MDVD
6.0 M x Vc = 0.500 M x 3.00 L
Vc = 0.25 L = 250 mL of 6.0M HCl
400 Solutions
Describe 3 ways of increasing the rate at which a substance
dissolves.
Answer
400 Solutions Answer
• Increase surface area
• Stirring/shaking
• Temperature change (usually increase temp)
Solutions 500
•
• Answer
Give the solubility of potassium nitrate at 500C. Estimate to the ones place.
Solutions 500
Answer:
82 g KNO3 / 100 g H2O