How much water must be added to a 25 mL sample of 1.5 M sodium sulfate in order to make it 0.20 M?

162.5 mL

Explanation:

M1*V1 = M2*V2

M - molarity

V - volume of solution

25*1.5 = 0.20 *V2

V2 = (25*1.5)/0.20= 187.5 mL of solution 2.

We had 25 mL of solution 1,  solution 2 should have volume 187.5 mL,

so we have to add V2 - V1 = 187.5 - 25 = 162.5 mL of water, or ≈ 163 mL

answer by yourhope:

how do models compare to real-world objects?

d. most models represent a real-world object in a simpler way.

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