A Chemist Needs 500 ML of a 20 MM Phosphate

Multiple Choice

A chemist needs 500 mL of a 20 mM phosphate buffer.The stock solution of the buffer is 100 mM.How much stock solution should be used to make the 20 mM phosphate buffer?

A) 100 mL
B) 1000 mL
C) 10 mL
D) 1.0 mL
E) 0.1 mL