Soran-University
Faculty of engineering
Chemical department
Viscometer
Prepared By
Supervised By
Huda Muslih Qadir
proff. Ibtisam kama
M.Widad and M.Maryam
Table of Contents
Introduction ................................................................................ 2
Materials , Equipment’s .............................................................. 4
procedure .................................................................................... 5
Calculation.................................................................................. 6
Data ............................................................................................ 7
Result .......................................................................................... 8
Discussion ................................................................................. 8
Conclusion .................................................................................. 9
Reference .................................................................................. 10
Table Of Figure
Figure 1
4
Figure 2
4
Figure 3
4
Figure 4
4
Figure 5
4
Figure 6
4
Figure 7
6
Figure 8
6
1
Aim
In this experiment we are going to use a viscometer for different liquids to find
time for each liquid
Measuring viscosity be viscometer
Introduction
A viscometer is a tool that is used to measure the viscosity of a material. By
measuring the viscosity, the viscometer is able to quantify the thickness or the
amount of internal friction of a material. During the test, the fluid material and the
test equipment are brought into contact with one another and the drag is used in the
viscosity calculation. Viscometers are instruments that measure the fluid flow and
viscosity of liquids. The viscosity of a liquid can affect its performance, whether
this is pumping or piping it, or how it performs for dipping and coating.
What is Viscosity?
Viscosity is the measure of how resistant a material is to motion when you apply
force to it.
For example, if you squeeze a tube of toothpaste, how easily does the contents
There is a formula for measuring viscosity:
Viscosity = sheer stress/shear rate.
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Kinematic Viscosity
Kinematic viscosity is the ratio of - absolute (or dynamic) viscosity to density - a
quantity in which no force is involved. Kinematic viscosity can be obtained by
dividing the absolute viscosity of a fluid with the fluid mass density like
ν=μ/ρ
Dynamic Viscosity
Dynamic viscosity is the force needed by a fluid to overcome its own internal
molecular friction so that the fluid will flow. The units of dynamic viscosity are:
Force / area x time
The Pascal unit (Pa) is used to describe pressure or stress = force per area
This unit can be combined with time (sec) to define dynamic viscosity.
3
Materials.
Crude Kerosene,
Water
Equipment’s
Graduation cylinder
Funnel
Viscometer
Thermometer
Stopwatch
Pycnometer
Figure 1
Figure 4
Figure 3
Figure 2
Figure 5
F
i g
u
r
e
1
Figure 6
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Procedure (about what were we doing from lab)
 First we need to prepare the laboratory balance, and the number on balance
must be zero.
 We bring the pycnometer and by laboratory balance we weight it, and should
be empty when measuring on the balance and we will get the weight of the
pycnometer in grams
 We found weight (mass) for each liquid for each liquids by this equation:
 First brought the viscometer
 Then we put some of the water in the graded cylindar
 Then we put the water in the viscometer a little bit and blow it on one side to
rise on the side to the specified location
 We pushed and we use our breath to pushed harder to in order the liquid rise
up to upper mark and the liquid rise up over the upper mark
 The are two things of the viscometer
• Upper mark indicating where sample is moved to by suction
• Lower marl representing original position which sample returns to
when suction force is released
 We should reduce the liquid point that is more than the right point
 It can not be one level
 We stop pushing
 the liquid get to the lower mark
 After that We find the time by viscometer
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Figure 7
Figure 8
Calculation :
Volume of pycnometer :50mL
Temperature:21℃
11.75+12.25+12.34
𝜇 water =
3
=12.11s
15.67+15.34+15.43
t c.kerosene =
3
=15.4
𝜇 c.kerosene =?
P water =?
Pc.kerosene =?
6
For density:
(m)liquids =∆𝑚 − 𝑒𝑚𝑝𝑡𝑦 𝑚𝑎𝑠𝑠 𝑜𝑓 𝑝𝑦𝑐𝑛𝑜𝑚𝑒𝑡𝑒𝑟
∆𝒎 𝒈
No
m empty gr
M liquid gr
P
𝒈𝒓
𝒄𝒎𝟑
water
83.5
33.3
50.2
1.004
Crude
73.1
33.3
39.8
0.796
kerosene
V =C .t …………………………… (1)
𝜇
V = ………………………………..(2)
𝑝
From (1) and (2) we found :
𝑝 2𝑡 2
𝜇2 = 𝜇1
𝑝 1𝑡1
………………….(3)
We use this equationto find viscosity crude kerosene :
𝑝 2𝑡 2
𝜇2 = 𝜇1
𝜇
𝑝 1𝑡1
1
P 1
t1
𝜇2
𝜇2
is viscosity of water =0.89 mpa.s
is density of water
p2
is flow time of water
t2
is viscosity of crude kerosene
is density of crude kerosene
is flow time of water
0.89∗0.796∗15.48
1.004∗12.11
= 0.902 mpa.s
Data
𝒈𝒓
liquid
density (
water
1.004
𝒄𝒎𝟑
)
time (s)
dynamic viscosity (mpa.s)
12.11 s
0.89 mpa.s
7
crude kerosene
0.796
15.48 s
0.902 mpa.s
8
Result
In this data above we found viscosity of crude kerosene and also need a density
both a material by pycnometer we need of them Some people put have a time even
time was a different after that we find the average time
We can find them by ostwald viscometer, To determine the relative viscosity of
given liquid using Ostwald’s viscometer
appear that viscosity kurde kerosene more than water because when density is
increase the viscosity is decrease
Discussion
What is the relationship between viscosity and temperature
What are the effects of temperature on viscosity In fluids the property of viscosity
is due to the cohesive force or. intermolecular forces of attraction. More these
forces more will be these molecules denying to flow. Hence more is the resistance
to flow ,which results more viscosity. Now if u increase the temperature of any
liquids the viscosity decreases. But if u consider gases then it's viscosity increases
with increase in temperature, which has a cause.
In case of liquids,with increase in temperature viscosity decreases
But in case of gases vicsosity increases with increase in temperature
There are two kinds of viscosity commonly reported, kinematic and dynamic.
Dynamic viscosity is the relationship between the shear stress and the shear rate in
a fluid. The Kinematic viscosity is the relationship between viscous and inertial
forces in a fluid.
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What are the error in viscometer?
The error associated from misalignment towards the unbounded sides of the
capillary (left to right) can be quite severe if the surface tension of the fluid (or
lack thereof due to surface contaminates on the capillary cell walls) allow sample
to "leak" out of the flow cell.
Conclusion
At this test we learned that how to determine the Measuring viscosity be
viscometer
We find the time by viscometer and find density by pycnometer,
A viscometer ) is an instrument used to measure the viscosity of a fluid. For liquids
with viscosities which vary with flow conditions
We have compared between the speed of water oil and soap and we’ve realized
that the speed of water is more than oil and soap and the speed of oil is more than
the soap .
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Reference :
• https://www.machinerylubrication.com/Read/29451/a
natomy-of-viscometer
• https://www.corrosionpedia.com/definition/6089/visco
meter
• https://www.quora.com/What-is-the-relationshipbetween-viscosity-and-temperature
• https://www.azom.com/amp/article.aspx?ArticleID=10
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