CE366 Experiment No. 1
Determination of Density of Common Liquids
Objective:
To determine the density of various liquids (water, oil, glycerin, etc.) using di;erent
methods and compare the results with standard values.
Learning Outcomes:
By the end of this experiment, students should be able to:
o
o
o
o
Understand the concept of density and its importance in fluid mechanics.
Measure the mass and volume of liquids accurately.
Calculate density using di;erent experimental methods.
Compare experimental results with standard values and analyze discrepancies.
Theory:
Density (ρ) is a fundamental property of fluids defined as mass per unit volume:
𝜌=
𝑚
𝑉
Where:
𝜌 = density (kg/m³ or g/cm³)
𝑚 = mass of the liquid (kg or g)
𝑉 = volume of the liquid (m³ or cm³)
The density of a liquid depends on temperature and pressure, but for most laboratory
applications, it is considered constant at standard conditions.
Apparatus and Materials:
o
o
o
o
Graduated cylinder (100 mL, 250 mL)
Electronic balance (precision ±0.01 g)
Hydrometer (for direct density measurement)
Thermometer
o Beakers (250 mL)
o Common liquids (distilled water, vegetable oil, glycerin, ethanol)
Procedure:
Method 1: Mass-Volume Measurement
1. Weigh the empty graduated cylinder using the electronic balance and record its mass
(𝑚!"#$% ).
2. Pour 100 mL of the test liquid (Ex: water) into the cylinder.
3. Weigh the cylinder with the liquid and record the total mass (𝑚$&$'( ).
4. Calculate the mass of the liquid:
𝑚()*+), = 𝑚$&$'( − 𝑚!"#$%
5. Compute the density:
𝜌=
𝑚()*+),
𝑉
6. Repeat for other liquids (oil, glycerin, ethanol).
Method 2: Hydrometer Method
1. Fill a tall cylinder with the test liquid.
2. Gently lower the hydrometer into the liquid and allow it to float freely.
3. Read the density value directly from the hydrometer scale at the liquid’s meniscus.
4. Record the temperature of the liquid (since density varies with temperature).
7. Data and Results:
(Sample)
Liquid
Volume
(mL)
100
Mass of
Empty
Cylinder
(g)
50
Mass of
Cylinder
+ Liquid
(g)
150
Water
Oil
100
50
Glycerin
100
50
Mass of Experimental Standard
Liquid
Density
Density
3
(g)
(g/cm )
(g/cm3)
100
1.0
130
80
0.80
225
175
1.75
0.998 (at
200C)
0.92
(varies
by types)
1.26 (at
200C)
% Error
0.20 %
12.04 %
38.89 %
Sample Computations:
For water:
𝜌=
150 𝑔 − 50 𝑔
𝑔
= 1.0
100 𝑚𝐿
𝑐𝑚-
%Error:
1.0 − 0.998
𝜌=.
. 𝑥 100 = 0.20 %
0.998
Discussion Questions:
1. Why does the density of a liquid change with temperature?
2. Compare the accuracy of the mass-volume method versus the hydrometer method.
3. What are possible sources of error in this experiment?
Conclusion:
Summarize the findings, compare experimental results with standard values, and discuss
possible reasons for discrepancies.
References:
- CHED CMO No. 91, s. 2017 (Civil Engineering Curriculum)
- Munson, B. R., Young, D. F., & Okiishi, T. H. (2013). *Fundamentals of Fluid Mechanics*.
Wiley.
Prepared by:
Felrem G. Lor
Civil Engineering Department
Cebu Institute of Technology-University
August 2025