Question

To detect the turbidity of the order of 0 to 10 ppm or 10 mg/l, the instrument used is

• A. Turbidimeter
• B. Jackson Turbidimeter
• C. Hallige Turbidimeter.
• D. Baylis Turbidimeter

Hint:

Different turbidimeters are suitable for different turbidity ranges. Jackson Turbidimeters are typically for high turbidity, while Nephelometric Turbidimeters (like those using the principle of light scattering, such as Baylis) are preferred for low turbidity measurements due to their higher sensitivity. Nephelometric Turbidity Units (NTU) are the standard units for modern turbidimeters for low turbidity.

Answer 1

The Correct Option is D

Step 1: Understand Turbidity Measurement.
Turbidity is a measure of the cloudiness or haziness of a fluid caused by individual particles (suspended solids) that are generally invisible to the naked eye, similar to smoke in air. It is an important parameter in water quality assessment. Different turbidimeters are designed for different ranges and types of turbidity measurements.
Step 2: Analyze the given turbidity range.
The question specifies detecting turbidity in the order of 0 to 10 ppm or 10 mg/l. This indicates a relatively low turbidity range, common for treated or clear raw water.
Step 3: Evaluate the suitability of each turbidimeter type for the given range.

• Turbidimeter (General): This is a general term for any instrument that measures turbidity. We need to identify a specific type suitable for the low range.
• Jackson Turbidimeter: This instrument is based on the principle of light extinction. It is suitable for measuring high turbidity values, typically above 25 Jackson Turbidity Units (JTU) or 25 ppm. It is not accurate for low turbidity.
• Hallige Turbidimeter: Also known as the Hellige Turbidimeter, this is a visual comparison turbidimeter often used for medium to high ranges, less precise for very low turbidities. It relies on comparing the sample's turbidity to standard turbid solutions.
• Baylis Turbidimeter: The Baylis turbidimeter, also known as the Photoelectric Turbidimeter, measures the scattering of light by suspended particles. It is known for its accuracy in measuring low turbidities, typically in the range of 0 to 10 ppm or 0 to 25 ppm (0 to 10 JTU or NTU). It is more sensitive and accurate for low turbidity measurements compared to visual methods.

Step 4: Select the correct instrument.
For detecting turbidity in the order of 0 to 10 ppm or 10 mg/l (a low range), the Baylis Turbidimeter is the most appropriate instrument due to its higher sensitivity and accuracy in this range. $$\boxed{\text{Baylis Turbidimeter}}$$