Monday Popquiz: Solubility and Concentration
1. ____________________ How many grams of
KBr are needed to make a saturated
solution in 100 g of water at 30 °C?
2. ____________________ In terms of
saturation, how would you classify a
KBr solution with a concentration of
90 g / 100 g of water at 50 °C?
3. ____________________ At what temperature
is the solubility of KBr the same as
that of KNO3?
4. ____________________ Which is more
soluble in water, NaClO3 or KBr? How can you tell?
5. Are any of the substances gases? Explain.
How do the following affect the process of dissolving, at a molecular level?
6. Stirring/shaking?
7. Breaking it into smaller pieces?
8. Heating the solvent?
9. Why is water a polar molecule?
10. Describe how/why Like Dissolves Like.
11. ____________________ What is the concentration of 42.1 grams of silver nitrate that
dissolves in 1750 mL of water?
12. ____________________ How many grams of salt will dissolve in 350 mL of water is
the solubility of salt is 35.9 g / 100 mL of H2O?
13. ____________________ If the solubility of KNO3 is 180 g / 100 mL of H2O, will 560 g
dissolve in 400 mL of H2O?
Monday Popquiz: Solubility and Concentration
72g
1. _____
_________ How many grams of
KBr are needed to make a saturated
solution in 100 g of water at 30 °C?
supersaturated_ In terms of
2. __
saturation, how would you classify a
KBr solution with a concentration of
90 g / 100 g of water at 50 °C?
(It’s holding more
than it usually
can….)
50 C
o
3. ____
________ At what temperature
is the solubility of KBr the same as that of KNO3?
4. _____
NaClO3_______ Which is more
You can
dissolve more at all temperatures, so it is more
soluble (tell me more than “the line is
higher”…tell me what that means when the line
is higher!
soluble in water, NaClO3 or KBr? How can you tell?
5. Are any of the substances gases? Explain.
No. If they were, the line would go down as
temp. goes up.
How do the following affect the process of dissolving, at a molecular level?
6. Stirring/shaking?
Moves molecules away, so more room for
interactions with solute.
7. Breaking it into smaller pieces?
More surface area for interactions
between water and solute molecules.
8. Heating the solvent?
Molecules of solute and solvent move
faster and interact more
9. Why is water a polar molecule?
Uneven distribution of electrons…one
side has a little positive charge (+) and one
side is a little negative (-)
10. Describe how/why Like Dissolves Like.
Polar things will dissolve in polar
solvents, nonpolar solutes will dissolve in
nonpolar solvents. Because the charges in a
polar molecule will pull apart the other if it also
has charges. (polar will pull apart polar, but not
nonpolar)
.024g/mL___ What is the concentration of 42.1 grams of silver
11. __
nitrate that dissolves in 1750 mL of water?
42.1 g
1750 mL
126 g___ How many grams of salt will dissolve in 350 mL of water is
12. ___
the solubility of salt is 35.9 g / 100 mL of H2O?
35.9 g
100mL
=
xg
350mL
yes__________ If the solubility of KNO3 is 180 g / 100 mL of H2O, will 560 g
13. ___
dissolve in 400 mL of H2O?
560 g
400mL
=
xg
100mL
x= 140 g, which is less than 180, so , yes.