Solubility and Concentration Review

Solubility and Concentration Review

Monday Popquiz: Solubility and Concentration

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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 youtell?

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

1. _____72g______How many grams of

KBr are needed to make a saturated

solution in 100 g of water at 30 °C?

2. __supersaturated_In terms of

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….)

3. ____50 oC______At what temperature

is the solubility of KBr the same as that of KNO3?

4. _____NaClO3______Which is more

soluble in water, NaClO3 or KBr? How can you tell?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!

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)

11. __.024g/mL___ What is the concentration of 42.1 grams of silver

nitrate thatdissolves in 1750 mL of water?

42.1 g

1750 mL

12. ___126 g___ 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?

35.9 gx g

100mL350mL

13. ___yes______If the solubility of KNO3 is 180 g / 100 mL of H2O, will 560 g

dissolve in 400 mL of H2O?

560 gx g

400mL100mL

x= 140 g, which is less than 180, so , yes.