1. What are other methods of moisture determination besides oven drying?
2. During the drying of samples, the weight is considered constant when the last two weights are within ± 0.0003 grams. What is the reason for this?
For #1, here is a site for you to read.
(Broken Link Removed)
For #2, could it have something to do with the sensitivity of your balance?
I really don't know, but what I know is that the balance has an uncertainty of ±0.0002 g.
1. Other methods of moisture determination besides oven drying include:
- Karl Fischer titration: This method involves the use of a specialized apparatus to determine the water content based on the reaction of water with iodine and sulfur dioxide.
- Infrared moisture balance: This technique uses infrared radiation to measure the moisture content of a sample by analyzing the absorption and reflection of the radiation.
- Microwave moisture analysis: In this method, microwaves are used to heat the sample, and the moisture content is determined based on the change in temperature.
- Chemical methods: Various chemical agents can be used to react with water and generate measurable changes, allowing for the determination of moisture content.
Regarding the link you provided for additional reading, it appears to be broken or not accessible. You can try searching for "moisture determination methods" online or referring to scientific journals and publications for more detailed information.
2. The requirement for the last two weights during drying to be within ± 0.0003 grams is likely related to the precision and sensitivity of the balance being used. This ensures that the weight readings are stable and consistent, providing a reliable indication that the sample has reached a constant weight.
If the weight difference between the last two measurements exceeds ± 0.0003 grams, it may suggest that the sample is still losing moisture, and additional drying time may be required. The sensitivity of the balance, which you mentioned to be ± 0.0002 grams, is within the acceptable range of precision for this purpose. By using a balance with high precision, the measurement can be conducted with greater accuracy and confidence in the results.