I've attached a picture not sure if it will work but i need with my science homework rlly

You would use C1V1=C2V2 to compare the concentration and volumes of two solutions. So we would plug in the given values and solve for the unknown

C1=.1
V1=21.5
C2=unknown
V2=25

(.1)(21.5)=x(25)
When you divide the left side by 25, you get 0.086 M

Hope this helps

chem is a bad profession to be enlisted too so you should just quit chem

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