The required volumes are;
1) 2 mL
2) 4 mL
3) 5 mL
Now we know that the dilution formula can be used to obtain the quantity of a solution that could be used in the preparation of another by the use of serial dilution. In this case, we can see that an aliquot of the solution is taken and then made up to mark in order to obtain the concentration that we require as we are trying to carry out the process of the serial dilution.
Now let us try to see how we can be able to prepare the solutions that are required as follows;
To prepare 50mM of of calcium nitrate;
C1V1= C2V2
C1 = initial concentration’
V1 = initial volume
C2 = final concentration
V2 = final volume
C1 = C2V2/C1
C1 = 20.0 mL * 5.00 mM/50mM
C1 = 2 mL
2) 20.0 mL * 1.00 mM/ 5.00 mM
= 4 mL
3) 20.0 mL * 0.250 mM/1.00 mM
= 5 mL
Learn more about serial dilution:https://brainly.com/question/13499062
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