Solutions Flashcards
A mixture that cannot be separated by a semipermeable membrane.
Solution.
A mixture that settles upon standing.
Suspension.
A mixture that contains particles that are small enough to pass through filters but are too large to pass through semipermeable membranes.
Colloid.
True or False:
A mixture can be classified as heterogeneous or homogeneous.
True.
True or False:
All solutions, by definition, are liquids.
False.
14 Kt gold is a solid solution (copper and silver). They can be solids, liquids or gasses.
A solution has 50.0 mL of ethanol and 10.0 mL of water. Which is the solute and which is the solvent?
Water solute, ethanol solvent.
Usually the higher volume component is the solvent.
A solution has 10.0 g of NaCl in 100.0 g of water. Which is the solute and which is the solvent?
NaCl solute, water solvent.
When a gas or solid is dissolved in water it is considered the solute and the water is the solvent.
A solution has 0.20 L of O2 and 0.80 L of N2. Which is the solute and which is the solvent?
O2 solute, N2 solvent.
Water is an excellent polar solvent and carbon tetrachloride (CCl4) is a nonpolar solvent. In which solvent is NaNO3 more likely to be soluble?
Water.
NaNO3 is an ionic compound, so it will be more soluble in water.
Water is an excellent polar solvent and carbon tetrachloride (CCl4) is a nonpolar solvent. In which solvent is I2 more likely to be soluble?
Carbon tetrachloride (CCl4).
I2 is non polar so would dissolved in non polar solvent.
Water is an excellent polar solvent and carbon tetrachloride (CCl4) is a nonpolar solvent. In which solvent is sucrose (table sugar) which is polar, more likely to be soluble?
Water.
Water is an excellent polar solvent and carbon tetrachloride (CCl4) is a nonpolar solvent. In which solvent is gasoline, which is nonpolar, more likely to be soluble?
Carbon tetrachloride.
True or False:
Ionic compounds will not be soluble in water, a molecular compound.
False.
Water is very polar so it is able to dissolve most ionic compounds! This is due to ion-dipole interactions.
If a crystal is added to a solution and it does not change size is it a saturated or unsaturated solution?
Saturated.
If a sugar cube completely dissolves when it is added to hot coffee is it a saturated or unsaturated solution?
Unsaturated.
Determine whether the following solution will be saturated or unsaturated at 20°C (the solubility of KCl is 34g/100mL at this temperature): adding 25 g of KCl to 100 g of water.
Unsaturated.
Determine whether the following solution will be saturated or unsaturated at 20°C (the solubility of NaNO3 is 68g/100mL at this temperature): addding 11 g of NaNO3 to 25 g of water.
Unsaturated.
Determine whether the following solution will be saturated or unsaturated at 20°C (the solubility of sugar is 82g/100mL at this temperature): adding 400 g of sugar to 125 g of water.
Saturated.
What role does temperature play in solubility?
Solids that are more soluble at higher temperatures form a supersaturated solution. This means the solution will have even more solute dissolved than if it were saturated.
These are unstable and will percipatate when disturbed.
A solution containing 80 g KCl in 200 g H2O at 50°C is cooled to 20°C. How many grams of KCl will remain in solution at 20°C?
Solubility data for KCl:
Solubility at 20°C = 34g KCl/100 g H2O
Solubility at 50°C = 43g KCl/100 g H2O
68 g of KCl.
Since 34g KCl can dissolve in 100g of H2O,
We have 200 g of water, therefore;
100 x 2 = 200 g
34 g x 2 = 68 g KCl.
A solution containing 80 g KCl in 200 g H2O at 50°C is cooled to 20°C. How many grams of KCl crystallized after cooling?
Solubility data for KCl:
Solubility at 20°C = 34g KCl/100 g H2O
Solubility at 50°C = 43g KCl/100 g H2O
12 g KCl.
Since we know that 68g of KCl can dissolve in 200 g of water at 20 degrees Celsius and we have 80 g of KCl when we started at 50 degree;
80 - 68 = 12 g.
True or False:
LiCl is soluble in water.
True.
It is an ionic compound.
True or False:
AgCl is soluble in water.
False.
Silver is insoluble. (PHAC Bud: Pb, Hg, Ag, Ca and Ba).
True or False:
BaCO3 is soluble in water.
False.
True or False:
K2O is soluble in water.
True.
True or False:
Fe(NO3)3 is soluble in water.
True.
True or False:
The solubility of most solids increases with increasing temperature.
True.
A sugar cube completely dissolves when it is added to hot coffee. Therefore the solubility of sugar ___________ with _________ temperature.
Increases, increasing.
True or False:
The solubility of all gases decreases with increasing temperature.
True.
True or False:
Pressure has no effect on the solubility of liquids or solids.
True.
It does affect the solubility of gas.
In general, the solubility of ________ in water decreases as temperature increases.
Gas.
Calculate the concentration of
nitrogen gas in water with a nitrogen gas at a partial pressure of 0.826 atm
above it. Henry’s law constant for
nitrogen in water is 6.8 × 10-4 mol/L-atm.
(0.826 atm)(.8 × 10-4 mol/L-atm) =
5.6 x 10^ -4