Answer:
40 mL
Step-by-step explanation:
To prepare a solution by a concentrated solution, we must use the equation:
C1xV1 = C2xV2
Where C is the concentration, V the volume, 1 is the initial solution and 2 the final solution. So, the final volume will be 250 mL, with 1.6% of concentration:
10xV1 = 1.6x250
V1 = 40 mL
So, it's necessary 40 mL of the SDS stock solution.