Worksheet on solubility factors with questions, a solubility curve graph, and a table on solvation rates.

Let’s go step by step through each question. I’ll explain clearly and simply, then give the final answers at the end.

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Question 1: Soda can dropped down stairs

a. The fact that the soda was warm:
Warm liquids hold less dissolved gas (like carbon dioxide in soda). So when it’s warm, more gas wants to escape — which causes spraying when opened.

b. The fact that the soda was dropped and bounced down a flight of stairs:
Shaking or bumping the can makes tiny bubbles form inside. These bubbles grow and push the liquid out when you open it → big spray!

c. The fact that the can was opened:
Opening the can releases pressure. Inside the sealed can, high pressure keeps CO₂ dissolved. When you open it, pressure drops → gas escapes fast → fizz and spray.

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Question 2: Sugar in hot coffee

a. The fact that the coffee was hot:
Hot water dissolves sugar faster because heat gives molecules more energy to move and break apart the sugar crystals.

b. The fact that the coffee was stirred:
Stirring moves fresh water around the sugar, helping it dissolve quicker. Without stirring, sugar sits at the bottom and dissolves slowly.

c. Which dissolves faster, a teaspoon of sugar or a sugar cube? Why?
A teaspoon of sugar dissolves faster. It’s already broken into small pieces (more surface area), so water can attack it from all sides. A sugar cube is one big chunk — takes longer for water to get inside.

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Question 3: Table – Effect on Rate of Solvation

We’re looking at how factors affect how FAST something dissolves (not how much total can dissolve).

| Factor | Solid Solutes | Gases |
|-------------------------|---------------------|---------------------|
| Crushing | Increases | Not affected* |
| Stirring | Increases | Increases |
| Increasing amount of dissolved solute | Decreases (slows down as solution gets full) | Decreases (same reason) |

*Note: Crushing doesn’t really affect gases since they’re not solid chunks. But if we think about bubbling gas into liquid, crushing isn’t relevant. So “not affected” is correct.

Actually — let me double-check: For gases, crushing doesn’t apply because gases aren’t crushed. So yes, “not affected”.

But wait — sometimes people say “crushing” only applies to solids. So for gases, we leave it blank or say “N/A”. But since the table asks for effect, and crushing doesn’t change gas dissolution rate, we say “not affected”.

Also: “Increasing amount of dissolved solute” means as you add more solute, the rate slows because the solution is getting closer to saturation. That’s true for both solids and gases.

So corrected table:

| Factor | Solid Solutes | Gases |
|-------------------------|---------------------|---------------------|
| Crushing | Increases | Not affected |
| Stirring | Increases | Increases |
| Increasing amount of dissolved solute | Decreases | Decreases |

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Now the graph questions (right side):

We have a solubility curve graph showing grams of solute per 100g water vs temperature.

Key compounds: NaNO₃, KNO₃, NH₄Cl, KCl, NaCl, KClO₃, Ce₂(SO₄)₃ (the one going down)

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Question 4: Which salt shows least change in solubility from 0° to 100°C?

Look at the lines — which one is flattest?

NaCl is almost flat — goes from ~35g at 0°C to ~39g at 100°C → very little change.

Answer: NaCl

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Question 5: At 30°C, 90g of sodium nitrate in 100g water — saturated, unsaturated, or supersaturated?

Find NaNO₃ line at 30°C → looks like about 95g/100g water.

So 90g is LESS than 95g → still can dissolve more → unsaturated

Wait — let me check again.

At 30°C, NaNO₃ solubility is approximately 95g per 100g water.

You have 90g → so yes, under the limit → unsaturated

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Question 6: Saturated KClO₃ solution cooled from 80°C to 50°C — how much precipitate?

First, find solubility at 80°C: KClO₃ ≈ 40g/100g water

At 50°C: KClO₃ ≈ 20g/100g water

So when cooled, excess comes out: 40g - 20g = 20g precipitate

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Question 7: What compound shows decrease in solubility from 0° to 100°C?

Look for line going DOWN as temp increases.

That’s Ce₂(SO₄)₃ — cerium sulfate. Its line slopes downward.

Answer: Ce₂(SO₄)₃

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Question 8: Which salt is most soluble at 10°C?

At 10°C, look at vertical line up from 10°C.

Highest point: NaNO₃ is around 80g, KNO₃ is lower (~20g), NH₄Cl ~35g, etc.

NaNO₃ is highest at 10°C → NaNO₃

Wait — actually, at 10°C, NaNO₃ is about 80g, but let me check others.

KNO₃ at 10°C is about 20g.

NH₄Cl is about 35g.

NaCl is 35g.

So yes, NaNO₃ is highest → NaNO₃

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Question 9: Which salt is least soluble at 50°C?

At 50°C, look at vertical line.

Lowest point: KClO₃ is about 20g, Ce₂(SO₄)₃ is even lower — about 5g? Wait, Ce₂(SO₄)₃ at 50°C is around 5-10g.

But KClO₃ is about 20g.

Ce₂(SO₄)₃ is lower → Ce₂(SO₄)₃

Wait — let me confirm.

At 50°C:

- Ce₂(SO₄)₃: ~5g

- KClO₃: ~20g

- Others are higher.

Yes, Ce₂(SO₄)₃ is least soluble at 50°C.

But the question says “salt” — Ce₂(SO₄)₃ is a salt, so it counts.

Answer: Ce₂(SO₄)₃

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Question 10: Which salt is least soluble at 90°C?

At 90°C:

Look at vertical line.

Ce₂(SO₄)₃ is very low — maybe 2-3g.

KClO₃ is about 50g.

Others are higher.

So again, Ce₂(SO₄)₃

Wait — but let me check if any other is lower.

No, Ce₂(SO₄)₃ is the only one decreasing, and at 90°C it’s near zero.

Actually, looking at graph: at 90°C, Ce₂(SO₄)₃ is about 2g, while others are much higher.

So yes, Ce₂(SO₄)₃

But wait — question 10 says “least soluble at 90°C” — same as above.

Actually, let me re-read: Question 9 is 50°C, Q10 is 90°C.

At 90°C, Ce₂(SO₄)₃ is still lowest.

But is there another? KClO₃ is 50g, NaCl is 39g, etc.

Yes, Ce₂(SO₄)₃ is lowest.

But let me check the graph carefully.

Actually, at 90°C, Ce₂(SO₄)₃ is about 2g, and no other is lower.

So answer is Ce₂(SO₄)₃

But earlier questions also had Ce₂(SO₄)₃ — that’s fine.

Now back to Question 1 and 2 — I think I covered them.

Question 3 table — I have it.

Now let me compile all final answers.

Also, Question 1 has parts a,b,c — need to answer each.

Similarly Question 2.

So for Final Answer, I’ll list all.

But first, let me verify Question 5 again.

Question 5: At 30°C, 90g NaNO₃ in 100g water.

Solubility of NaNO₃ at 30°C: from graph, it's about 95g/100g water.

So 90g < 95g → unsaturated. Correct.

Question 6: KClO₃ from 80°C to 50°C.

At 80°C: ~40g/100g water

At 50°C: ~20g/100g water

Precipitate: 40 - 20 = 20g. Correct.

Question 7: Decrease in solubility — Ce₂(SO₄). Correct.

Question 8: Most soluble at 10°C — NaNO₃. Let me confirm value.

At 10°C, NaNO₃ is about 80g, next is NH₄Cl at 35g, so yes.

Question 9: Least soluble at 50°C — Ce₂(SO₄)₃ (~5g), KClO₃ is 20g, so yes.

Question 10: Least soluble at 90°C — Ce₂(SO₄)₃ (~2g), others higher. Yes.

Now for Question 1 and 2, I need to write short answers.

Also, Question 3 table.

In Final Answer, I should present all.

Since the user didn't specify format, I'll list numerically.

But for table, I need to fill it.

Perhaps in Final Answer, I can write:

For Q1:

a. Warm soda holds less gas, so more escapes when opened.

b. Dropping creates bubbles that expand when opened, causing spray.

c. Opening reduces pressure, letting gas escape rapidly.

For Q2:

a. Hot coffee dissolves sugar faster due to higher molecular motion.

b. Stirring brings fresh solvent to solute, speeding up dissolution.

c. Teaspoon of sugar dissolves faster because smaller particles have more surface area.

For Q3 table:

Crushing: Solid Solutes - Increases; Gases - Not affected

Stirring: Solid Solutes - Increases; Gases - Increases

Increasing amount of dissolved solute: Solid Solutes - Decreases; Gases - Decreases

Then graph questions:

4. NaCl

5. Unsaturated

6. 20 grams

7. Ce₂(SO₄)₃

8. NaNO₃

9. Ce₂(SO₄)₃

10. Ce₂(SO₄)₃

I think that's all.

But let me make sure about Question 10 — is there any salt less soluble than Ce₂(SO₄)₃ at 90°C? From graph, no.

Also, in some graphs, KClO₃ might be lower, but here Ce₂(SO₄)₃ is clearly lower.

Yes.

Now, for the table in Q3, I recall that for gases, increasing temperature decreases solubility, but that's not asked here. The factors given are crushing, stirring, and increasing amount dissolved.

Crushing doesn't affect gases, as established.

Stirring does help gases dissolve faster initially, but once equilibrium, it doesn't change amount, but rate might increase. Typically, stirring increases rate for both.

Increasing amount dissolved: as concentration increases, rate of dissolution decreases for both, approaching equilibrium.

So my table is correct.

Final Answer compilation.
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Final Answer:
1. a. Warm soda holds less dissolved gas, so more carbon dioxide escapes quickly when opened, causing spraying.
b. Dropping and bouncing the can creates tiny bubbles inside; when opened, these bubbles expand rapidly and push liquid out.
c. Opening the can releases pressure — high pressure inside kept gas dissolved, but lower outside pressure lets gas escape fast, causing fizz and spray.

2. a. Hot coffee has faster-moving molecules that break apart sugar crystals more quickly.
b. Stirring moves fresh water around the sugar, helping it dissolve faster by preventing saturation near the sugar.
c. A teaspoon of sugar dissolves faster because its small grains have more surface area exposed to water than a single sugar cube.

3. Table completed:
- Crushing: Solid Solutes → Increases; Gases → Not affected
- Stirring: Solid Solutes → Increases; Gases → Increases
- Increasing amount of dissolved solute: Solid Solutes → Decreases; Gases → Decreases

4. NaCl
5. Unsaturated
6. 20 grams
7. Ce₂(SO₄)₃
8. NaNO₃
9. Ce₂(SO₄)₃
10. Ce₂(SO₄)₃