You need a 5 microgram glucose/ml aqueous solution, but the lab balance is accurate to only 0.01g (ie., it displays 2 digits to the right of the decimal point) Describe 2 methods by which you could accurately prepare this solution using the lab balance.
I don't know what to do at all, so you convert the micrograms to grams and then find it that way? please help
Yes, one method to accurately prepare the 5 microgram glucose/ml solution using the lab balance is by converting micrograms to grams. Here's an explanation of the steps:
Method 1: Converting micrograms to grams
1. Start by converting the desired concentration of glucose from micrograms to grams. Since there are 1,000,000 micrograms in a gram, divide 5 micrograms by 1,000,000 to get the equivalent value in grams: 5 micrograms / 1,000,000 = 0.000005 grams.
2. Take a small container, such as a beaker or weighing boat, and place it on the lab balance.
3. Tare or zero the balance to account for the weight of the container alone.
4. Slowly add glucose to the container until the lab balance displays a weight of 0.000005 grams.
Method 2: Dilution
Another method involves diluting a stock solution of glucose to obtain the desired concentration. Here's a step-by-step guide to this method:
1. Obtain a stock solution of glucose with a known concentration, preferably higher than 5 micrograms/ml.
2. Dilute the stock solution by a calculated factor to achieve the desired concentration. For example, if your stock solution concentration is 50 micrograms/ml, you can dilute it by a factor of 1/10 to obtain 5 micrograms/ml:
- Take a clean container, such as a volumetric flask, and add 1 part (e.g., 1 ml) of the stock solution.
- Add 9 parts (e.g., 9 ml) of a suitable solvent, such as distilled water, to the flask. This will result in a total volume of 10 ml, with a final concentration of 5 micrograms/ml.
3. Thoroughly mix the solution to ensure proper dilution and uniform distribution of the glucose.
4. If you need a higher volume of the solution, you can scale up the dilution by maintaining the same ratio of stock solution to diluent.
Remember, it is important to handle any lab equipment and chemicals properly and adhere to safety guidelines. Consult with a lab professional or supervisor for specific instructions and precautions in your lab environment.