[fransmile]

Hello,

I just started my grad school and they assigned some chem questions to brush up on our skills.  I really forgot how to answer these questions and I would really appreciate if someone could help me out.  I don't need the answers, I just want to understand how to do them.  Thank you for your *delete me*!!

1. Describe how you would make a 400 ml solution of a 20% w/v sucrose solution. MW of sucrose = 342.3

2. Given a 1M TrisHCl pH 8.0 and 0.5M EDTA solution, how would you make 50ml of a TE solution (10mM TrisHCl pH 8.0 and 1.0mM EDTA).

[Borek]

First: don't crosspost.

I really forgot how to answer these questions and I would really appreciate if someone could help me out.

I will use my CASC (see footer), it does such things faster then you wink.

1. Describe how you would make a 400 ml solution of a 20% w/v sucrose solution. MW of sucrose = 342.3

MW in not necessary for % calculations. You need a solution that will have 400 mL volume, and that will contain 20% of 400 grams of sucrose.

2. Given a 1M TrisHCl pH 8.0 and 0.5M EDTA solution, how would you make 50ml of a TE solution (10mM TrisHCl pH 8.0 and 1.0mM EDTA).

Calculate amounts of both reagents in the final solution. Calculate what volumes of known solutions will contain these amounts of substances. Fill up to 50 mL with water.