WATER LAB
OBJECTIVE:
Water is everywhere. It makes up about 3/4ths of the surface of the earth. It makes up 50-95% of the
weight of living organisms. It is in the air we breathe, the sinks we use and in every cell of the body.
Water has special properties that make it unusual and complex. For instance, think about what water can
do by answering these questions:
1. How does water rise from the roots of a tree to the very top?
2. How do insects walk on the water?
3. Why does ice float rather than sink?
4. Why do people become seriously ill, or die, if they go without liquid for a week or so?
5. How would life in a lake be affected if ice sank and lakes froze from the bottom up?
Water has the ability to be a liquid, solid or gas depending on the temperature at which it is found. Each
molecule of water is made up of 2 hydrogen and 1 oxygen atoms bonded together.
Water is attracted to other water molecules like magnets. This is called cohesion.
Water has several unusual properties that set it apart as one of the most unique substances on Earth, and
certainly one of the most important! The hydrogen bonding that occurs between molecules results in
much higher melting points and boiling points as well as a much lower vapor pressure; this allows water
to exist at temperatures that make life on our planet possible. In this lab, we will use a variety of common
household items and substances to look into some of the more peculiar aspects of this important chemical.
PART A: PHASE CHANGES OF WATER DEMO
Materials:
GLX Datalogger
Temperature Probe
Thermometer clamp
Ring stand
Ice
Hot plate
250 mL beaker
Water
Procedure:
1. Your teacher will fill the 250 mL beaker no more than half-way with ice water
(combination of ice and water).
2. The mixture will be heated gradually over medium heat and stirring
occasionally.
3. The GLX datalogger will record the temperature at one minute intervals.
4. Continue to heat the water and record the temperature until the water has been
boiling for 5 minutes. Note: Do not let the beaker go dry, turn the heat off
before the water has all boiled off.
5. Copy the graph of the data collected at the end of the lab and answer the
following questions.
Figure 1
Part A: Phase Changes of Water QUESTIONS (Answer in COMPLETE SENTENCES)
1. What time did the ice melt completely? __________________________________________
2. When did your water start to boil? ______________________________________________
3. What happened to the temperature of the water as the ice melted? As the water boiled?_____
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
4. Why do you think the temperature did not change? Where was the energy from the hot plate
going?_____________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
PART B: MODELING THE WATER CYCLE
Materials:
Goggles
Hot plate
250 mL beaker
ice
1 evaporating dish
water
Clock/Stopwatch
Goggles
Procedure:
1. Put 100 mL of water in a 250 mL beaker. Cover the beaker with an evaporating dish or a
large watch glass.
2. Put the beaker on a hot plate. CAUTION: Be careful not to spill the water. Fill the
evaporating dish with ice.
3. Turn the hot plate on to medium. Observe what is happening in the beaker and
evaporating dish every two minutes for a total of 10 minutes.
4. Record your observations by drawing pictures of your set-up in the table.
Time: 0 minutes
Time: 2 minutes
Time: 4 minutes
Time: 6 minutes
Time: 8 minutes
Time: 10 minutes
Modeling the Water Cycle QUESTIONS (Answer in COMPLETE SENTENCES!)
1. Sketch the water cycle and label CONDENSATION, EVAPORATION, GROUNDWATER,
PRECIPITATION, RUNOFF, and SURFACE WATER.
2. What source of energy drives the water cycle in your model? _________________________
______________________________________________________________________________
3. What energy source does this correspond to in Earth’s water cycle?_____________________
______________________________________________________________________________
4. What is the effect of the ice in your model? _______________________________________
______________________________________________________________________________
______________________________________________________________________________
5. What part of the water cycle does the ice help to model (Be specific)?___________________
______________________________________________________________________________
______________________________________________________________________________
6. As water evaporates, what will happen to the concentration of any substances dissolved in
the water? Will it increase or decrease?___________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
7. How does evaporation affect the concentration of salts in the ocean?___________________
______________________________________________________________________________
______________________________________________________________________________
PART C: PROPERTIES OF WATER
Follow the procedures at each of the following stations. Record all observations and
measurements. (Answer in COMPLETE SENTENCES!)
Station A: Drowning Lincoln
Station B: Floating a Paperclip
Station C: Climbing Water?
Station D: Sink or Float
Station A: Downing Lincoln
Part 1:
Materials:
Penny
Water
Pipette
Graduated Cylinder
Procedure:
1. Obtain a pipette and a small graduated cylinder. Make sure the pipette is clean.
2. Using the pipette, count how many drops it takes to get 1 mL in the graduated cylinder.
a. How many drops, of the size produced by your pipette, are in 1 milliliter of water?
___________________________________________________________________________
___________________________________________________________________________
b. Conversely, how much water is in each drop? (Divide 1mL by the number of drops).
On average _________________________________________________________________
___________________________________________________________________________
3. Predict how many drops you will be able to put on the penny before it overflows by having each
person at your table guess.
4. Now, let’s see how many drops of water you can place on the surface of the penny before it
overflows. Drop water from the dropper onto the penny, keeping a careful count of each drop.
5. Draw a diagram showing the shape of the water on the penny after one drop, when the penny is half
full and just before it looks like it is going to overflow.
6. How many total drops did you get on the penny? _________________drops.
7. If the number of drops is different from your prediction, explain your results in terms of
cohesion.__________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
Station A: Drowning Lincoln
Part 2:
Materials:
Penny
Water
Pipette
Detergent
Procedure:
1. With your finger, spread ONE DROP of detergent on the surface of a dry penny.
2. How many drops do you think this penny will hold after being smeared with detergent?
3. Using the same dropper as before, add drops of water to the penny surface. Keep a careful count
of the number of drops, and draw pictures as before.
4. Did the detergent have an effect on the outcome?_______________________________________
5. How does the detergent affect the water?_____________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
6. Explain how detergents act as cleaning agents._________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
Station B: Floating a Paper Clip
Floating a Paper Clip
Materials:
Paper cup
Water
Paperclip
Salt
Procedure:
1. Obtain a paper cup and a small paper clip.
2. Fill the paper cup to the edge with tap water.
3. Carefully slide the paper clip onto the surface of the water. Record your observations.
Observations:___________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
4. Why do you think the paper clip was able to stay on the surface of the water? ________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
5. Remove the paper clip and add approximately ½ teaspoon of salt to the water in the paper cup.
6. Repeat step #3 using the salt solution. Record your observations.
Observations: __________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
7. What property of water allowed the paper clip to be placed on its surface? Was this property
affected by the presence of dissolved salt?____________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
Station C: Climbing Water?
Materials:
Water
Chromatography Paper Strip
Stop Watch
Graduated Cylinder
Vis-A-Vis Marker
Ruler
Procedure:
1. How fast do you think that water will climb up a piece of absorbent paper about ½ in. wide?
_____________________________________________________________________________
_____________________________________________________________________________
2. Obtain a 50 ml graduated cylinder, and tear off a strip of chromatography paper that is just long
enough to hang over the side of the cylinder (inside) and reach the bottom.
3. Place a single drop of ink from a Vis-a-Vis pen on the paper about one inch from the bottom and
let it dry.
4. Place 10ml of water into the graduated cylinder and place the strip of paper in the cylinder so the
bottom end is immersed in water and the drop of ink is just above the surface of the water. Fold
the paper over the top of the graduated cylinder.
5. Note the starting time.______________
6. At 5-minute intervals, record the distance that the ink has travelled by holding a ruler up to the
side of the graduated cylinder. When water climbs to the tip of the paper, remove it and let it dry.
7. How did the ink change?__________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
8. Why did this occur? Think about capillary action.______________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
Station D: Sink or Float?
Part A – Water & Oil
Materials:
Water
Graduated Cylinder
Oil
Procedure:
1. Put 8 ml of water into a 10 ml graduated cylinder.
2. What will happen if you add cooking oil?_____________________________________________
______________________________________________________________________________
3. Gently add 2 ml of cooking oil by tilting the cylinder of water slightly and letting the oil run
slowly down the inside of the cylinder.
4. What happened?_________________________________________________________________
______________________________________________________________________________
5. Save the graduated cylinder with its contents and get a clean 10 ml cylinder for the next
experiment.
6. Draw the contents of the graduated cylinder.
Part B – Oil & Water
Materials:
Water
Graduated Cylinder
Oil
Procedure:
1. Place 8 ml of oil into a 10 ml graduated cylinder.
2. What will happen when you add water?______________________________________________
______________________________________________________________________________
3. Gently add 2 ml of water by tilting the cylinder of oil slightly and letting the water run slowly
down the inside of the cylinder.
4. Which is less dense (meaning which has less weight per ml), oil or water? How do you know?
______________________________________________________________________________
______________________________________________________________________________
Part C – Water, Oil and Dye
Materials:
Food Coloring Dye
Graduated Cylinders from 4a & 4c
Procedure:
1. Predict what will happen if you add a few drops of water-soluble dye solution to each of the
above graduated cylinders containing water and oil. Will the dye mix with the water, the oil or
both?__________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
2. Perform the experiment. Add a few drops of dye to each cylinder. Use a glass-stirring rod to
penetrate the interface between each layer, giving the dye access to both water and oil. How does
the dye behave in each cylinder? Does it diffuse into the oil? Into the water?_________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
3. Will the contents remain mixed?____________________________________________________
Conclusion:
1. List three things that you discovered about water.
a. ___________________________________________________________________________
b. ___________________________________________________________________________
c. ___________________________________________________________________________
NAME_________________________________________________ DATE___________ PERIOD_____
WATER PRE-LAB
Completely read through the Water Lab and answer the questions below.
PART A: Phase Changes of Water
The difference between solid, liquid, and
gas phases of matter is the heat energy
they contain. Liquids have more energy
than solids and gases have more energy
than liquids.
Phase changes include melting, freezing,
vaporization, condensation, deposition,
and sublimation.
Phase changes are physical changes because physical properties are altered but the substance
remains the same kind of matter.
1) Examine Figure 1 to the left. Why do you think
the graph flattens out between ice & water and water
& steam? Where is the energy going? (Hint see the
diagram above left)
_______________________________________
_______________________________________
_______________________________________
_______________________________________
PART B: Modeling the Water Cycle
1) What provides the energy source to drive the water cycle in nature?
___________________________________________________________________________
2) What provides the energy source to drive the simulated water cycle in your lab?
___________________________________________________________________________
3) What is the purpose of covering your beaker with a watch glass / evaporating dish filled with
ice?
___________________________________________________________________________
4) What part of the water cycle does this model?
___________________________________________________________________________
PART C: Properties of Water Notes: Take notes about some of the unique properties of water.
Cohesion:
Surface Tension:
Capillary Action / Adhesion:
Density of Water: What is the density of liquid water?__________________________________
How does the density of water change as it changes phase?___
__________________________________________________
__________________________________________________
Match the correct letter to section of the water cycle.
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Condensation
Evapotranspiration
Ground-water discharge
Infiltration
Snowmelt runoff to streams
Stream flow
Surface runoff
Water storage in ice and snow
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Evaporation
Freshwater storage
Ground-water storage
Precipitation
Spring
Sublimation
Water storage in the atmosphere
Water storage in oceans