Name:
Directions: Answer these questions before you begin the Activity.
1. Name two ways that the thermometer could be damaged while doing this activity.
2. Why should you wear gloves when performing this activity?
3. What safety symbols are associated with this lab?
4. What affect do you think adding salt to water will have on the boiling point of the
water?
5. Explain how you convert temperatures from Celsius to Kelvin.
Adding small amounts of salt to water that is being boiled to cook pasta and
adding antifreeze to a radiator have a common result—increasing the boiling
point.
What You’ll Investigate
How much can the boiling point of a solution be changed?
Materials
distilled water (400 mL)
Epsom salt, (72 g)
Bunsen burner
Celsius thermometer
ring stand
250-mL beaker
Procedures
1. Bring 100-mL of distilled water to a gentle boil in a 250-mL beaker. Record
the temperature in Table 1.
2. Dissolve 12 g of Epsom salt in 100 mL of distilled water. Bring the solution to
a gentle boil and record its boiling point in Table 1.
3. Repeat steps 2, adding 12 g (24 g total) of Epsom salt. And again adding 12
grams (total of 36 g.)
4. Using Create-A-Graph Classic graph your results. (The boiling point is the
dependent variable, the amount of Epsom Salt is the independent variable.)
Data
Table 1
The Effects of Solute on Boiling
Water
Grams of Solute
0
12
24
36
Boiling Point
(C)
Boiling Point
(K)
PLACE GRAPH HERE
1. Explain the difference between the boiling points of pure water and a water
solution.
2. Instead of doubling the amount of NaCl in step 3, what would have been the effect
of doubling the amount of water?
3. Predict what would happen if you continued to add more salt. Would your graph
continue in the same pattern or eventually level off? Explain your prediction.