PENGGUNAAN VISKOMETER DALAM PENGUJIAN VISKOSITAS | FARMASI FISIKA - STFI Bandung

Summary

In this video tutorial, Wahyu Priyo Legowo explains how to measure viscosity using three different viscometers: the Brookfield ARV (for high viscosity), the Brookfield LV (for low viscosity), and the Ostwald viscometer (for liquids like syrups and oils). The video covers the setup, usage, and calculation methods for each tool, providing clear instructions on how to measure viscosity accurately. The tutorial is designed to help students perform online practical experiments, offering step-by-step guidance and useful formulas for calculating viscosity in various fluids.

Takeaways

• 😀 The video explains how to use different types of viscometers (Brookfield and Ostwald) to measure viscosity.
• 😀 Brookfield viscometers come in three types: RV for medium viscosity, LV for low viscosity, and high-viscosity models.
• 😀 Viscosity measurements on Brookfield viscometers are displayed in units like MPa or cP, depending on the instrument and sample.
• 😀 To use the Brookfield viscometer, you need to select the correct spindle (R1, R2, or R3) and RPM for accurate readings.
• 😀 For the LV (low viscosity) Brookfield viscometer, you need to manually convert the analog readings using a table and a formula.
• 😀 The Ostwald viscometer is used to measure the viscosity of liquid samples like oils, syrups, or emulsions.
• 😀 To measure viscosity using the Ostwald viscometer, the time it takes for the liquid to pass between two marks is recorded and used in a formula.
• 😀 When using the Ostwald viscometer, ensure that the liquid sample is placed in the chamber properly and measure the time using a stopwatch.
• 😀 For accurate viscosity calculations, use a reference liquid's viscosity (e.g., water) in the formula for comparison with the sample.
• 😀 The video also emphasizes how to use practical equipment for online laboratory experiments, providing students with a way to learn from home.

Q & A

What is the purpose of this video?

The video aims to explain the tools used to measure viscosity in various substances for online practical learning, specifically targeting students who are studying at home.

What are the three types of viscometers commonly used in Indonesia?

The three types of viscometers commonly used in Indonesia are the Brookfield Viscometer (with RC, RV, and LV types), and the Ostwald Viscometer.

What is the difference between the RC, RV, and LV types of the Brookfield Viscometer?

The RC type is used for high viscosity fluids, the RV type is used for medium viscosity fluids, and the LV type is used for low viscosity fluids.

How is the Brookfield Viscometer used to measure viscosity?

The Brookfield Viscometer measures viscosity by immersing a spindle into the fluid sample and rotating it at a specified speed (RPM). The viscometer then displays the viscosity value in units of mPa.s (millipascal seconds).

What does an error or '0' reading on the Brookfield Viscometer display indicate?

An error or '0' reading on the Brookfield Viscometer display indicates that the viscosity of the fluid is either too low or too high for the chosen spindle to measure accurately.

What type of samples is the LV type Brookfield Viscometer used for?

The LV type Brookfield Viscometer is used to measure low viscosity fluids, such as pharmaceutical preparations like creams or ointments.

How is the viscosity value calculated using the LV Brookfield Viscometer?

The viscosity value is calculated by multiplying the reading on the analog dial (which shows the viscosity in terms of dial units) by a factor from a conversion table, depending on the spindle number and RPM setting.

What is the purpose of the Ostwald Viscometer?

The Ostwald Viscometer is typically used for measuring the viscosity of liquid substances such as syrups, emulsions, or oils, which are commonly used in oral pharmaceuticals.

How is viscosity measured using the Ostwald Viscometer?

Viscosity using the Ostwald Viscometer is measured by timing how long it takes for a fluid to pass between two marks in the viscometer tube. The time is then used in a formula to calculate viscosity.

What is the formula used to calculate viscosity with the Ostwald Viscometer?

The viscosity formula for the Ostwald Viscometer is: Viscosity = (ρ1 × T1) / (ρ2 × T2) Where ρ1 and ρ2 are the densities of water and the sample fluid, T1 and T2 are the times for water and the sample fluid to pass between the two marks.