Question

Calculate the density of paraffin oil, if a glass capillary of diameter 0.25mm dipped in paraffin oil of the surface tension 0.0245N/m rises to a height of 4cm. (Angle of contact of paraffin oil with glass is 28° and g=9.8m/m?).

Answer 1

Answer:

The density of paraffin oil is : 882.86kg/m3

using the formula : h = 2TcosФ/rβg

where:

h = capillarity rise

T = surface tension

β = density

r = radius of the capillary tube

∅ = angle of contact

Explanation:

meaning of capillarity and surface tension

capillarity is the rise and fall of liquid in a narrow capillarity tube. the rise and fall of the liquid depends on the surface tension, the diameter of the bore, density, acceleration due to gravity and angle of contact.

meaning of angle of contact

angle of contact helps to know if liquid in a capillary tube will spread or form droplets on the surface of the capillary tube. if the angle is acute, liquid will spread, if obtuse, droplets are formed.

given data:

T = 0.0245N/m

r = diameter/2 = 0.25/2 = 0.125mm convert to metre which is =           0.125 x$10^{-3}$

∅ = 28°

g = 9.8m/$s^{2}$

h = 4cm = 4 x $10^{-2}$

therefore:

density(β) = $\frac{2Tcos\phi }{hrg}$

density($\beta$) =  $\frac{2*cos28\ }{0.004*10*0.000125}$ = 882.86kg/m3

in conclusion, the density of parrafin oil is : 882.86kg/m3

learn more about capillarity : https:// brainly.com/question/2664027

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