We have that you make 340 mL of a 4 M solution by dissolving 20M stock solution in 68ml water
From the question we are told
How do you make 340 mL of a 4 M solution from a 20 M stock solution
Generally the equation for the Molarity is mathematically given as
M1V1=M2V2
Therefore
20*x=4*340
x=68ml
Therefore
you make 340 mL of a 4 M solution by dissloving 20M stock solution in 68ml water
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