saturation

saturated vs. unsaturated solutions

The maximum amount of sugar that will dissolve in a liter of 20 C water is 2000 grams. A sugar-water solution that contains 1 liter of water and 2000 grams of sugar is said to be saturated. A saturated solution is a solution that contains as much solute as can dissolve in a given solvent at a given temperature. If you add more than 2000 grams of sugar to a liter of 20 C water, the extra sugar wont dissolve. On the other hand, a solution containing less than 2000 g of sugar in 1 liter of 20 C water can hold more sugar. A solution that contains less solute than can dissolve at a given temperature is called an unsaturated solution. You can learn more about saturated and unsaturated solutions by watching the video at this URL: .

saturation depends on the solute

The Figure 1.1 shows the amounts of several different solutes that will dissolve in a liter of water at 20 C. As you can see from the graph, solutes vary greatly in how soluble they are in water. For example, you can dissolve almost 20 times as much sugar as baking soda in the same amount of water at this temperature. Q: Assume that a solution contains 150 grams of Epsom salt in 1 liter of water at 20 C. Is the solution saturated or unsaturated? A: A saturated solution of Epsom salt in 1 liter of 20 C water would contain 250 grams of Epsom salt. Therefore, this solution is unsaturated. It can hold another 100 grams of Epsom salt. Q: What do you think would happen if you added more than 250 grams of Epsom salt to a liter of 20 C water? A: Any Epsom salt over 250 grams would not dissolve in the solution.

textbook_image

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questions

there is a limit on how much of any substance will dissolve in a given amount of another substance.

-->  a. true

b. false

which sugar-water solution is saturated?

a) 1000 g of sugar in 1 l of water at 20 c

b) 1500 g of sugar in 1 l of water at 20 c

-->  c) 2000 g of sugar in 1 l of water at 20 c

d) all of the above

which saltwater solution is unsaturated?

-->  a) 358 g of salt in 1 l of water at 20 c

b) 359 g of salt in 1 l of water at 20 c

c) 360 g of salt in 1 l of water at 20 c

d) none of the above

you could dissolve more sugar in a saturated sugar-water solution by heating the water.

-->  a. true

b. false

diagram questions

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