Boiling Point Lab Use the cheat sheet to help
you complete your lab report!!
Boiling Point Lab Report
PURPOSE: The purpose of this
experiment is to determine the amount of salt in an
unknown water sample by determining its boiling point
Boiling Point Lab Report
BACKGROUND INFO: List and describe details you
know about boiling, boiling water, adding salt to water,
etc.
Boiling Point Lab Report
HYPOTHESIS: By examining the unknown,
take a guess as to the amount of salt per 200 mL. (You can do this after you
get in lab)
Boiling Point Lab Report
MATERIALS & EQUIPMENT: You can list these materials
after using them in lab There are a few safety
concerns which will be covered later
What is the purpose of the Boiling Point Lab?
0%
0%
0% 1. To heat water to the highest temperature possible
2. To evaporate all the water from a salt water mixture
3. To identify the amount of salt in an unknown mixture
Boiling Point Lab Procedures
1. Measure 200 mL of water & put it in flask2. Add salt (this will vary) – 0 g FIRST TRIAL3. Dissolve salt by swishing flask around4. Insert thermometer & heat on hot plate5. Measure temp every minute (Table 1)6. Temp will stop rising at boiling point (Table
2)7. Take off hot plate using flask tongs8. Do not dump hot water. Let it cool.9. Repeat procedure using different flask
Boiling Point Lab Safety Concerns
Hot plates, heated glass & water may cause severe burns – Be cautious
Hot glass & cold glass look exactly the same – Assume it is hot!!
Keep cords from hanging over table to prevent snagging and hot liquid
spills Do not put face or any body parts
directly over flask opening
Boiling Point Lab Safety & Equipment Concerns
When in the same area as anyone heating liquid, you must wear goggles
(THIS IS STATE LAW) Never put anything into water when it
is boiling Hot plates are for heating liquids only
(Any student using them improperly will be dismissed WITHOUT warning)
Boiling Point Lab Equipment Safety
Never expose thermometers or other equipment to LARGE TEMPERATURE CHANGES – especially not glass!!! Keep cords away from hot plate
Use the flask tongs to remove the flask from the hot plate (DO NOT ATTEMPT TO USE TONGS TO DUMP OUT HOT LIQUID!!) Wait until the liquid cools enough to
dump out by hand
What is the purpose of the Boiling Point Lab?
0%
0%
0% 1. To heat water to the highest temperature possible
2. To evaporate all the water from a salt water mixture
3. To identify the amount of salt in an unknown mixture
How much water should go in the flask for each trial?
0%
0%
0%
0% 1.Fill it up2.100 mL3.200 mL4.Doesn’t matter
How should the hot water be dumped out?
0%
0%
0% 1.Using the lab tongs, dump it while still hot so that it can be used immediately
2.Grab the flask by hand from the hot plate and dump it
3.Remove the flask with tongs, set it down until cool enough to dump by hand
Standard Lab Rules 1.) Stay on task
2.) Use equipment properly 3.) Clean up after yourself
Do you understand and agree to abide by the lab rules & procedures for personal & equipment safety in this experiment?
0%
0% 1.Yes2.No
Boiling Point Lab Are you ready?
OR Re-test?
What is the purpose of the Boiling Point Lab?
0%
0%
0% 1.To heat water to the highest temperature possible
2.To evaporate all the water from a salt water mixture
3.To identify the amount of salt in an unknown mixture
How much water should go in the flask for each trial?
0%
0%
0%
0% 1.Fill it up2.100 mL3.200 mL4.Doesn’t matter
How should the hot water be dumped out?
0%
0%
0% 1.Using the lab tongs, dump it while still hot so that it can be used immediately
2.Grab the flask by hand from the hot plate and dump it
3.Remove the flask with tongs, set it down until cool enough to dump by hand
Do understand and agree to abide by the lab rules & procedures for personal & equipment
safety in this experiment?
0%
0% 1.Yes2.No
Do understand and agree to abide by the lab rules & procedures for personal & equipment
safety in this experiment?
0%
0% 1.Yes2.No
Boiling Point Lab Finishing up the lab report
Boiling Point Lab Procedures
1. Measure 200 mL of water & put it in flask2. Add salt (this will vary) – 0 g FIRST TRIAL3. Dissolve salt by swishing flask around4. Insert thermometer & heat on hot plate5. Measure temp every minute (Table 1)6. Temp will stop rising at boiling point (Table
2)7. Take off hot plate using flask tongs8. Do not dump hot water. Let it cool.9. Repeat procedure using different flask
Results
Explain what the data tables and graph show plus any other
significant observations Be specific as to why the data
tables & graphs were included as well as what you learned
from the data
Table 2Boiling Points
Determine the temperature at which the salt-water mixture stopped rising.
Record this as the boiling point for each mixture
tested.
What is the independent variable in this experiment?
0%
0%
0%
0% 1.Boiling Point2.Amount of Salt3.Temperature4.Time
What is the dependent variable in this experiment?
0%
0%
0%
0% 1.Boiling Point2.Amount of Salt3.Temperature4.Time
Variables What are some controlled variables in this experiment? What are some variables
that could have been controlled better?
Graph 1Boiling Point vs. Amount of
Salt Amount of salt on x-axis
(measured in grams) Temperature on y-axis
(measure in degrees Celsius) Plot points
Draw line of best fit Determine where boiling point of
unknown intersects the line
Results
Explain what the data tables and graph show plus any other
significant observations Be specific as to why the data
tables & graphs were included as well as what you learned
from the data
Analysis
Be sure to share how much salt you believe there is in the
unknown mixture. Be sure to mention possible
sources of error in the experiment (variables not
controlled really well would be great to mention here)
Approximately how much salt did you estimate is in the unknown?
0%0%0%0%0%0%0%0%
1 2 3 4 5 6 7 8
1. 0 g2. 5 g3. 10 g4. 15 g5. 20 g6. 25 g7. 30 g8. 35 g
Boiling Point Lab Report
Finish up Lab Report When finished turn in or if not,
then finish ON YOUR OWN & turn in Monday!!
Turn in your remotes