Question

MUTLTIPLE CHOICE QUESTION:If you wanted to make 50 mL of 35 mM NaCl solution by diluting a 3.5 M stock solution of NaCL, how many microlitres of the stock solution would you use? a) 10 b)500 c)5000 d)100 e) 5

Answer 1

Since the number of mole of NaCl is the same
M1V1 = M2V2
(50/1000) (35x10^-3) = 3.5 V
1.75x10^-3 = 3.5V
V = 5x10^-4 L = 500 microlitres