**See the two Related Questions to the left for complete
instructions on how to make any solution of any
concentrations.**

To make a 1 in 4 dilution, it is best is to use a graduated
cylinder. Measure out 3 parts water and add to that 1 part stock
solution, which gives a total of 4 parts. For instance, if you
measure out 30 mL of water, and then add 10 mL of stock solution to
that, you will have a total of 40 mL solution, 1/4 the
concentration of the original stock solution. (Or, equivalently if
you need more than this, measure out 150 mL of water and add 50 mL
of stock solution to give a total of 200 mL of the diluted
solution). If you don't have a graduated cylinder, you'll need two
containers: one small and one much larger. Fill the small one
completely with water, and then pour that into a new (larger)
container. Do that two more times (for a total of 3). Then fill the
smaller container with stock solution, and add the water. When
diluting acids and bases, it is extremely important to add the
acid/base to water, and not the other way around! If you want to do
a dilution with different numbers, just change the numbers
accordingly. For example, if you want a 2 in 5 dilution, add 3
parts water to 2 parts stock solution. When it says "2 in 5" that
means two parts stock solution to 5 total parts, so that leaves 3
parts water!