Question

1. Your lab uses 8M sucrose for its experiments. There is a stock bottle with 250mL of aqueous 10M sucrose. Set up equation you would use to figure out how to prepare 60 mL of 8M sucrose in water.

2. How would you make 300 mL of a 1:3 dilution of oil in water?

3. How would you prepare 500 mL of 6% glucose from a 30% glucose solution?

Answer 1

1. you can use formula

Volume required * concentration required/ concentration given

Hence,

Required volume= 60ml

Required concentration= 8M

Concentration given= 10M

Therefore, (60ml)* (8M)/ (10M) = 48ml

48 ml stock solution and 12 ml water makes 60ml, 8M sucrose solution

2. For 1:3 oil into water preparation for 300 ml.

Let say you have to prepare 100ml of 1:3 oil in water solution. Then add 25ml oil in 75 ml water.

Similarly for 300 ml,

25*25*25 three times = 75 ml oil

And

75*75*75 three times water =225ml

Add 75 ml oil in 225 ml water which makes your solution 1:3 oil in water solution

3. The equation, Volume required* concentration required/ concentration given also used for this condition,

Required volume= 500ml

Required concentration (%)= 6%

Concentration given= 30%

Hence, (500ml) * (6%)/ (30%) = 100ml

100ml solution and 400ml water will makes 500ml of 6% glucose solution