Saturated, unsaturated and supersaturated solutions
Grade 10 Science Worksheet - Building Confidence
Circle the best answer, or write your answer on the line.
Baking soda dissolves up to 9.6 g per 100 g of water at 20 °C. A cup of 100 g of water at 20 °C holds 5 g. How many more grams could dissolve, Bo?
Sugar dissolves up to 200 g per 100 mL of water at 25 °C. A jar of 100 mL of water holds 150 g. How many more grams could dissolve, Kira?
Salt's limit is 36.0 g per 100 g of water at 25 °C. A cup at 25 °C holds 36.0 g in 100 g of water. Which is it, Luz?
- Unsaturated: a few more grams of salt will still dissolve
- Saturated: it holds as much as it can
- Supersaturated: the salt is past its limit
Sugar's limit is 200 g per 100 mL of water at 25 °C. A cooled, clear solution holds 250 g per 100 mL at 25 °C. Which is it, Milo?
- Saturated: it sits right at its sugar limit
- Supersaturated: above the limit, and unstable
- Unsaturated: it could still hold even more sugar
What does a saturated solution mean, Noah?
- It holds the most solute that can dissolve at that temperature
- It holds more solute than its usual limit allows at that temperature
- It holds so much solute that it has turned to a solid block
Salt crystals stay undissolved at the bottom of a well-stirred cup of salt water. What does that show, Pia?
- The solution is supersaturated, since solid is left over
- The solution is saturated
- The solution is unsaturated, since the crystals are new
Why is a supersaturated solution unstable, Ren?
- Its undissolved crystals keep growing larger on the bottom
- It holds less solute than it can, so it slowly dries out
- It holds more than it can keep dissolved, so crystals can form
A salt crystal is dropped into an unsaturated salt solution. What happens, Tala?
- It dissolves, since there is still room
- Many new crystals form around it at once
- It sits on the bottom, since the solution is full
A salt crystal is dropped into a saturated salt solution at the same temperature. What happens, Zee?
- It dissolves completely, as it would in plain water
- It sits undissolved, since no more can dissolve
- Crystals shoot out through the whole cup at once
A sugar crystal is dropped into a supersaturated sugar solution. What happens, Esme?
- It dissolves, since the solution still has room left
- Extra sugar crystallizes out around it
- Nothing happens, just as in a saturated solution