To make 4.25 L of 3.0 M NaOH solution how much of a 9.0 M NaOH solution would be needed?

1.41 L

Explanation:

Initially the concentration of NaOH was 9.0M (say M1) finally the concentration becomes 3.0M (say M2)

intial volume (say V1) is to be calculated when the final volume (say V2) is 4.25L

we have,

M1V1=M2V2

or V1=(M2V2)/M1= 3.0×4.25/9.0= 1.41L

Hence 1.41 L of 9.0M solution is required to prepare 4.25L of 3.0M NaOH solution

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explanation: