Science 8
Lab Skills
Here are the steps for measuring volume with a graduated cylinder or a burette:
Beakers and flasks are only used for estimated (approximate) volumes. They are
not used when accurate measurements are needed.
Graduated cylinders and burettes are a round glass tube with volume markings.
When filled with a liquid, the volume can be read by using the markings.
How to read:
1. Place graduated cylinders on a flat surface.
Place burettes in a clamp on a ring stand.
2. Place your eye level with the liquid's surface
3. Read the bottom of the meniscus (curve in the
top of the liquid)*
The flow of liquid through a burette is controlled by turning the stopcock.
When the stopcock is horizontal, the flow rate is stopped. When the
stopcock is vertical, the maximum flow is allowed.
Title
Name and Class
Date
Fluids Lab #1
Determining Flow Rate
PLAN
I am working with ___________________.
To stay safe in this lab, we will
To clean up, we will
Introduction/Theory
Flow rate = volume of liquid (mL)
Time
Purpose
In this investigation, we will practice calculating flow rate, and also investigate
the relationship between the height of a column of water and the flow rate of
liquid from it.
Hypothesis
PREDICT: Do you think the flow rate will increase, decrease or stay the same as
the amount of water in the burette goes down?
Materials Refer to:
Burette, ring stand, burette clamp, water, beaker, watch with a second hand
Procedure Refer to:
1. Fill the burette exactly to the highest graduation (tick mark).
2. Have one partner use a watch or timer to measure how long it takes for 10ml
of water to run out of the burette with the stopcock fully open (vertical).
3. Calculate the flow rate in ml/s.
4. Repeat steps #1-3 to obtain flow rates with the height of water starting each
time with 10 ml less
Refill the burette and repeat the measurement to obtain three trials.
Observations (what I saw)
Trial #1
Initial
Volume
Volume
of
of water Water
in the
that
burette
Flows
(ml)
out (ml)
50
10
Time
(s)
Trial # 2
Trial #3
Calculate Volume Time Calculate Volume Time Calculate
Flow Rate
of
(s)
Flow Rate
of
(s)
Flow Rate
(ml/s)
Water
(ml/s)
Water
(ml/s)
that
that
Flows
Flows
out (ml)
out (ml)
10
10
40
10
10
10
30
10
10
10
20
10
10
10
10
10
10
10
Average Flow
Rate (ml/s)
Analysis (What I think happened)
Using the average flow rate data, create a graph showing the relationship
between the volume of water in the cylinder and the flow rate.
What pattern do you notice in the data?
Why do you think this occurs?
What types of situations involve water or other fluids flowing from different heights?
How might this relationship be important in different technologies?
Conclusion
Write a brief summary of what you learned about the relationship between flow
rate and the height of water in a column.