# math

posted by .

you need to prepare 5ml NaCl solution . you already have a stock solution of 10% NaCl that you are asked to use . how many ul NaCl solution would you need to make 5ml of a 2% NaCl solution?

• math -

You want 1/5 the concentration, so you need 5 times the volume.

So, use 4 parts water and 1 part 10% NaCl.
That is, use 1mL NaCl and 4mL H2O

## Similar Questions

1. ### science-chem

first, thanks so much Bob for helping me!!!! Q4.you will be asked to prepare 25.0 mL of a 0.019 M solution of sodium chloride during this experiment.... a.calculate mass of sodium chloride needed to prepare solution. (0.25L)(0.019M …
2. ### science

Q4.you will be asked to prepare 25.0 mL of a 0.019 M solution of sodium chloride during this experiment.... a.calculate mass of sodium chloride needed to prepare solution. (0.25L)(0.019M NaCl/L)*(58.5g NaCl/1mole NaCl)=0.278 g NaCl....is …
3. ### chemistry

How many mL of a 0.90% (m/v) NaCl stock solution will you need to to prepare 250 mL of a 0.225% m/v NaCl solution?
4. ### bio

You have a sample of NaCl that contains 100 mg/ml NaCl. You are trying to perform an reaction that requires 10ml of 20 mg/ml. Enter in the correct amount (in ml) of Stock NaCl solution you need to use to make 10ml of 20 mg/ml NaCl
5. ### chemistry

A student needs to make a dilution from a stock solution. The stock solution is 2.) M NaCl. How much should the student use of the 2.0 M NaCl to make 1.0 L of 0.05M NaCl diluted stock.
6. ### science

In the lab you need to make 1.00 L of a 0.300 M NaCl solution. You had previously made a 0.950 M NaCl solution that you can dilute to form your new solution. How many mL of the concentrated solution would you use to make the dilute …
7. ### Chemistry

What is the molarity of a solution of Mg(OH)2 if the solution contains 1.35 g in exactly 100 mL of solution?
8. ### Math

How would you go about making 250ml of a 20X stock solution of NaCl to dilute later to a final concentration of 50mM?