A researcher needs 800 mL of a 25 mM phosphate buffer.The stock solution of the buffer is 100 mM.How much stock solution should be used to make the 25 mM phosphate buffer?
A) 31 mL
B) 310 mL
C) 200 mL
D) 2.0 mL
E) 0.2 mL

Question

Quizplus · Accepted Answer

To prepare a diluted solution, use the formula C1V1 = C2V2. Here, C1 = 100 mM, V1 = ?, C2 = 25 mM, V2 = 800 mL. Solving for V1 gives V1 = (C2 * V2) / C1 = (25 mM * 800 mL) / 100 mM = 200 mL.

A Researcher Needs 800 ML of a 25 MM Phosphate