Department: Petroleum Engineering Title: Hydrometer Prepared by: Muhammad S. RaniYah Style: Harvard Subject: Fluid Mechanics

1. Soran University
Faculty of Engineering
Department of Petroleum Engineering
Fluid Mechanic
Title: Hydrometer
Experiment No.: 1
Name: Muhammad Sulaimon Rasul
Group: B2
Date: 1 OCT 2019
Supervisors: Sarkar Mhedin, Rawezh Najat, Mr. Shahab, Ms. Shagul

2. Contents
Aim………………………………………………………………………………………….…….1
Theory…………………………………………………………………………………….…….…1
Apparatus…………………………………………………………...…………………………..…2
Procedure………………………………………………………………………………………….3
Calculation………………………………………………………………………………...………4
Result and Discussion……………………………………………………………………………..5
Conclusion………………………………………………………………………………………...5
References…………………………………………………………………………………………6
List of Figures
Fig1. A 500ml Cylinder ………………………………………………………………………….2
Fig2. Hydrometer ………………………………………………...………………...…………….2
Fig3. Diesel ………………………………………………………………...…………………….2
Fig4. Salt …………………………………………...…………………………………………….2
Fig5. An aerometer …………………………………………….…………………………………3
List of Tables
Table 1: Experimental and Theorical Results……………………………………………………..5

3. Aim
The aim of experiment is to find the density and mass of three fluids (water, diesel, salt water)
using mathematical calculation and hydrometer.
Theory
One of experimental ways to finding density of a fluid is from a specific gravity of that fluid which
is one of the physical properties of material. Scientists are using this property to indicate the type
of fluids and their behaviors. Relative density or Specific Gravity (SG) is the ratio of unknown
fluid to the density of water at standard temperature and pressure (Andreas, 2001).
A common method used to determine the specific gravity of a fluid which it uses an instrument
known as hydrometer, which is a hallow glass designed to float over various densities. The reading
scale while the aerometer how much sinks to the fluid will provide a calibrated scale of specific
gravity of that fluid. The dimeter of the stem is a dependence of the hydrometer at how much its
sensitive and a large and bulb and thin stem hydrometers are more sensitive. Hydrometers are float
more on heaver fluids than lighter liquid. (Suhaimi, 2002)
The principle work of hydrometer is that body (the aerometer) based on Archimedes principles
which immersed in a fluid which floated up by a force of buoyancy that equals to the weight of
the displacement fluid which basically measures the weight of displaced fluid by the volume of
aerometer. The specific gravity is dimensionless and can be shown as the equation below (eq 1)
(Avogadro's Lab Supply, Inc., 2019):
𝑆. 𝐺 =
𝑊𝑒𝑖𝑔ℎ𝑡 𝑜𝑓 𝐹𝑙𝑢𝑖𝑑
𝑊𝑒𝑖𝑔ℎ𝑡 𝑜𝑓 𝑊𝑎𝑡𝑒𝑟
……………….…………………………………………Eq.1
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4. Apparatus and Materials
Materials: Fresh Water (500 ml), Diesel (500 ml), Salt
Apparatus and Equipment’s: 500ml Cylinder, (0.8-0.9 ml) Hydrometer, (0.9-1.0 ml) Hydrometer,
(1.1-1.2 ml) Hydrometer.
Fig1. A 500ml
Cylinder: Measures
water volume in (ml).
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Fig2. Hydrometer: Is a device
used to measure specific gravity
and has many types depending
on fluid density range.
Fig3. Diesel: is a
material has lower
density than water.
Fig4. Salt: Is a material
composed of NaCl and used to
mix with water.

5. Procedure
1. The first step should three cylinders of 500ml be prepared and each one fill till 500ml of
water, diesel, and salt should be mixed with a fresh water inside one of cylinders and should
give 500ml for each one.
2. Now put 0.8-0.9 Hydrometer inside diesel carefully and read it when it gets floated on
water. After it stops moving, read the line on hydrometer. It was 0.818x1g/cc=0.818g/cc.
3. Again, do the same procedure as above just use 0.9-1.0 for Fresh water. The calculated
density was 0.996 g/cc.
4. For salt water also the same just use 1.1-1.2 hydrometer and read it. It has 1.134g/cc when
its density calculated.
5. Finally, find mass of each one using density formula which has done in the calculations.
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Fig5. An aerometer has put in four different fluids which each one has its density.

6. Calculation
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7. Result and Discussion
Table 1: Experimental and Theorical Results
Materials Volume (cc) Density (g/ml) Mass (gm)
Fresh-Water 500 0.996 498
Salt Water 500 1.134 567
Diesel 500 0.818 409
The Density of water is 1gm/cc at 10Co
but the results on the table was made on nearly 26Co
and
that’s why it’s 0.996g/cc. But the salt water should be 1.023g/cc at 26 Co
but may it has exceeded
the amount of salt concentration. The density of Diesel can be change between 0.8 to 0.86
depending on room temperature and pressure. Regarding to the aerometer A at figure 5, it seems
the first liquid has nearly 0.82 gm/cc of density and its actually lower compare to water and it
could be diesel as well. At picture B the number that can be read is 1.05gm/cc which its denser
than water so it could be sea water. For Picture C also the density is more than water around 0.15
gm/cc which may also be the sea water depending on salt concentration. The last one at picture D
is 0.996 gm/cc which can be fresh water. In order to make the procedure more accurate, performing
this kind of tests should be in a standard condition (at temperature of 60F and at 1 atmosphere
(Atm)).
Conclusion
Performing this kind of experiment’s make students engage more and gain ability to distinguish
between hydrometers and be able to use them for finding specific gravity of fluids then using a
formula to get a density and mass of the fluid.
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8. References
Alexandrou, A. (2001). Principle of Fluid Mechanics. New Jersey.
Avogadro's Lab Supply, Inc. (2019). How To Use A Hydrometer. [online] Available at:
https://www.avogadro-lab supply.com/content/How_To_Use_A_Hydrometer/2https://www.avogadro-
lab-supply.com/content/How_To_Use_A_Hydrometer/2 [Accessed 7 Oct. 2019].
Suhaimi Abu Talib, (2002). Fluid Mechanics, Penerbit Anda.
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