Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears...
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Transcript of Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears...
![Page 1: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/1.jpg)
Saturation
![Page 2: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/2.jpg)
Dissolving
• Does sodium chloride dissolve in water?
• Yes
• How do we know?
• It disappears into the water. It is still there because the sodium chloride returns when a salt solution evaporates.
![Page 3: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/3.jpg)
What happens at the particle level when sodium chloride
dissolves?
• The kinetic energy of moving water particles breaks individual particles off the crystals of salt.
• The salt particles are attracted to water particles and the salt particles move into the water.
![Page 4: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/4.jpg)
In Part 1 you added a 2-mL spoon of salt to 30 g of water.
The salt dissolved.
• What do you think would happen if you added another 2-mL spoon of salt? Would it dissolve?
• Is there a limit to the amount of a substance that will dissolve in a measure of water?
![Page 5: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/5.jpg)
If so, is the amount of a substance that will dissolve in a measure of water the same
for all substances?
![Page 6: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/6.jpg)
![Page 7: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/7.jpg)
Work with your group
• Create a plan to answer the three questions.
• Look at the bottle I have
• I have a supply of these bottles with caps and these large scoops. You may want to use one or more in your plan.
![Page 8: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/8.jpg)
Discuss a Plan
• What makes a good plan• Put a measured volume (mass) of water
in one of the bottles• Put in salt. Cap the bottle and shake
until all of the salt dissolves.• Add more salt by scoops until you have
used all the salt or solid salt accumulates on the bottom of the bottle.
![Page 9: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/9.jpg)
Plan
• Determine how much salt actually dissolved in the water
• Repeat the procedure with a second solute and compare.
![Page 10: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/10.jpg)
How Much Will Dissolve?
• LM page 78
• Read the questions silently as I read aloud.
• The questions are posed in a context of 30g (mL) of solvent (water) and two solutes are used table salt and Epsom Salts (NaCl and MgSO4).
![Page 11: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/11.jpg)
Hints• Make the solutions in bottles with caps to prevent
spilling.• Shaking will speed up the dissolving• Use self-stick notes to label the two bottles. Stick
them to the bottles at the water level for reference later
• 2 students might take charge of the NaCl and 2 take the MgSO4
• The dry funnel can be used to guide the salts efficiently into the bottle
• Dry the end of the funnel with a bit of paper towel if it gets even a singe drop of liquid on it
![Page 12: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/12.jpg)
Gather Data
• General Rule
• If you are not sure if the solid dissolved add another scoop and shake.
![Page 13: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/13.jpg)
Saturation
• When you dissolve a solid substance in water until no more will dissolve, the solution is a saturated solution.
• If you continue to add solid material to a saturated solution, the solid will simply pile up on the bottom of the container.
![Page 14: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/14.jpg)
Saturated Solutions
• Did sodium chloride and magnesium sulfate dissolve in water? What is your evidence?
• Less solid material is observable on the bottom of the bottles than was placed in the bottles with the water.
• The final volume of liquid in the bottles is significantly greater than the starting volume.
![Page 15: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/15.jpg)
Were you able to make a saturated sodium chloride
solution? What is your evidence?
• Yes
• The solution has un-dissolved sodium chloride on the bottom.
![Page 16: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/16.jpg)
Were you able to make a saturated magnesium sulfate
solution? What is your evidence?
• Yes
• The solution has un-dissolved magnesium sulfate on the bottom.
![Page 17: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/17.jpg)
Did the amount of liquid in the bottles change? Why?
• Yes,
• The volume of the solution increased because the solute dissolved and entered the solvent.
• The solute occupies space, so the volume of the solute plus solve increased.
![Page 18: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/18.jpg)
Did the amount of water in the bottles change?
• No
• No water was added or removed
• The change in volume was due to added solute, not added water.
![Page 19: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/19.jpg)
Did it take the same amount of sodium chloride and
magnesium sulfate to saturate 30g of water?
• No
• It took a lot more magnesium sulfate to make a saturated solution.
![Page 20: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/20.jpg)
How many grams of sodium chloride and how many grams
of magnesium sulfate are needed to saturate 30g of
water?
![Page 21: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/21.jpg)
Find a solution
• Discuss with your group how to find a better solution to this problem.
• 5 minutes
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30g of water, an unknown mass of substance dissolved in
the water, and an unknown mass of substance that is not
dissolved.• Filter out the un-dissolved material with a coffee
filter. The saturated solution passes through the filter.
• Weigh the saturated mass and subtract from 30g.• The difference is the mass of the substance
dissolved in the water.
![Page 23: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/23.jpg)
Complete the inquiry
• Lab Manual
• “How Much Will Dissolve?” B sheet
• CLEAN UP
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Share results
• Complete lab manual page 79
![Page 25: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/25.jpg)
![Page 26: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/26.jpg)
What happened when the first scoop of NaCl was added to
the bottle of water?• The water particles banged into the crystals
of salt and broke particles of sodium chloride free.
• The NaCl particles were attracted to the water particles.
• The salt particles moved into the volume of water surrounded by water particles
![Page 27: Saturation. Dissolving Does sodium chloride dissolve in water? Yes How do we know? It disappears into the water. It is still there because the sodium.](https://reader035.fdocuments.us/reader035/viewer/2022062321/56649f0e5503460f94c22f4f/html5/thumbnails/27.jpg)
Class work
• Complete lab page “Deeper Thoughts” section
Homework
Complete Response Sheet -Solutions LM page 81