Question

If 250 mL of a 0.50 M NaCl solution is diluted to 840 mL, what is the molarity of the resulting solution?

a) 0.15 M
b) 6.7 M
c) 0.60 M
d) 1.7 M
e) 0.0025 M

Answer 1

Convert all the mL to L first, .25 L and .84 L (.25) (.5) = (.84) (x) solve... I got .148809524, round to one sig fig (i think) would be .1 M

Answer 2

Answer: a) 0.15 M

Step-by-step explanation:

According to the dilution law,

`M_1V_1=M_2V_2`

where,

`M_1` = molarity of stock solution = 0.50 M

`V_1` = volume of stock solution = 250 ml

`M_2` = molarity of diluted solution = ?

`V_2` = volume of diluted solution = 840 ml

Putting in the values, we get:

`0.50M* 250=M_2* 840`

`M_2=0.15`

Therefore, the molarity of the resulting solution is 0.15 M