Question about using the Wihelmy blade method

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SUMMARY

The discussion centers on the Wilhelmy blade method used to measure interfacial tension, specifically for a paracetamol compact submerged 0.12 m in water. A force of 0.21 mN was recorded, leading to the conclusion that the interfacial tension between the paracetamol blade and water is 58.6 mN/m. The contact angle was debated, with values of 19.15 mN/m and 32.15 mN/m mentioned, but the correct calculation method using the equation COSθ = F/P * ƔLV is emphasized. Surface tension was incorrectly stated as 23 in/dyn, which requires conversion to mN/m for accurate interpretation.

PREREQUISITES
  • Understanding of the Wilhelmy blade method
  • Knowledge of interfacial tension and surface tension concepts
  • Familiarity with the equation COSθ = F/P * ƔLV
  • Ability to convert units between in/dyn and mN/m
NEXT STEPS
  • Research the Wilhelmy plate method in detail
  • Learn how to accurately convert surface tension units from in/dyn to mN/m
  • Study the relationship between contact angle and interfacial tension
  • Explore practical applications of interfacial tension measurements in pharmaceuticals
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This discussion is beneficial for chemists, materials scientists, and researchers involved in surface chemistry, particularly those working with pharmaceutical compounds and interfacial phenomena.

havenly
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Homework Statement
the wihelmy blade method
Relevant Equations
COSθ= F/P* ƔLV
for the wihelmy blade method we want to measure the interfacial tension exerted on a paracetamol compact in the shape of a rectangular parallepiped perimeter submerged 0.12 m in water we measure a force of 0.21 mN for a contact angle of 88.29°

answer whether they are true or false

Surface tension is 23 in/dyn
la tension interfaciale entre la lame de paracetamol et l'eau est 58,6mN/m
the contact angle between the paracetamol blade and the water 19.15mN/m
the contact angle between the paracetamol blade and the water is 32.15m/mNI think that the interfacial tension is 58.6mN/m because of question c I do not understand how to calculate the contact angle between the paracetamol sheet and the water
 

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havenly said:
Homework Statement:: the wihelmy blade method
Relevant Equations:: COSθ= F/P* ƔLV

answer whether they are true or false

Surface tension is 23 in/dyn
la tension interfaciale entre la lame de paracetamol et l'eau est 58,6mN/m
the contact angle between the paracetamol blade and the water 19.15mN/m
the contact angle between the paracetamol blade and the water is 32.15m/mN
It seems to be a simple problem of converting 23 inch/dyne to meter/milliNewton.

Please, see:
https://en.wikipedia.org/wiki/Wilhelmy_plate

https://www.researchgate.net/profile/Virginija_Jankauskaite/publication/285514136/figure/fig1/AS:670019541295122@1536756515903/Schematic-representation-of-Wilhelmy-plate-method.png