Hardness Test Kit - TK3012-Z

Summary

This video demonstrates how to perform a total hardness drop count test using the endpoint ID procedure. It emphasizes the importance of gathering an accurate sample, rinsing the vial to prevent contamination, and using a white background for better visibility during the test. Key steps include adding five drops of hardness buffer, one scoop of hardness indicator powder, and swirling the vial after each addition. The titration process is completed when the sample color changes from red to blue, indicating the presence or absence of hardness in the water sample.

Takeaways

• 🧪 Accurate sampling is crucial for precise results in the hardness drop count test.
• 🚿 Rinse the vial three times with the test sample to avoid contamination from previous titrations.
• 👁️ Hold the vial at eye level to ensure you collect an accurate sample.
• 📏 Place the vial on a level surface and check it again at eye level for precision.
• 🔳 Using a white background, like a paper towel, helps in observing color changes more clearly.
• 💧 Add 5 drops of hardness buffer by holding the bottle vertically to ensure consistent drop size.
• 🔄 Swirl the vial after adding each reagent to ensure proper mixing of the chemicals.
• 🧂 Add one scoop of hardness indicator powder and dissolve it fully by swirling; the sample turning red indicates hardness is present.
• 🔵 If the sample turns blue, no hardness is present, and the test is complete.
• 🧴 Use the correct titrant and sample size, and hold the titrant bottle vertically for consistent drop size during titration. The test is complete when the color changes from red to blue.

Q & A

What is the first step in performing a total hardness drop count test according to the endpoint ID procedure?

The first step is to gather an accurate sample. It's important to rinse the vial three times with the sample to minimize contamination.

Why is it important to rinse the vial before gathering the sample?

Rinsing the vial three times with the sample to be tested minimizes the chance of contamination from a previous titration.

How can you ensure the sample size is accurate?

Hold the vial close to eye level when filling it, and then place it on a level surface, bending down to eye level to verify accuracy.

What is the purpose of using a white background during the titration?

A white background, like a cabinet tray or white paper towel, provides contrast, making it easier to see the color changes during the titration.

What is added after gathering the sample, and how should it be applied?

Five drops of hardness buffer are added. The buffer should be applied by holding the bottle vertically to ensure consistent drop size.

Why is it important to swirl the vial after adding each reagent?

Swirling ensures that the reagents are properly mixed, which is critical for the accuracy of the test.

What happens after adding the hardness indicator powder?

The sample is swirled to dissolve the powder. If the sample turns red, it indicates that hardness is present. If the sample turns blue, it indicates no hardness is present, and the titration is complete.

What is the next step if the sample turns red after adding the hardness indicator powder?

The next step is to perform the titration by adding titrant drop by drop and swirling the vial after each drop until the sample changes from red to blue.

Why is it important to check the equivalency and sample size on the titrant bottle?

The titrant bottle is manufactured for specific equivalency and sample sizes, so it is essential to verify that you are using the correct titrant for the sample size.

When is the titration complete according to the endpoint ID procedure?

The titration is complete when the sample changes color from red to blue, indicating that the hardness has been neutralized.