61,132 views
30 votes
30 votes
How much water needs to be added

to 55 mL of 3.0 M stock solution to
produce a .75 M solution?

User Gamrix
by
2.7k points

2 Answers

8 votes
8 votes

Answer:

gotta concert mL to L

3.0=mol/0.055( you multiply morality and liter)

0.165 mol

you divide the mole by the other given molarity

0.165/0.75= 0.22 L

0.22 *1000= 220 mL

Step-by-step explanation:

User Filippo Vicari
by
2.9k points
14 votes
14 votes

Answer:

165 ml

Step-by-step explanation:

We are given;

Initial volume; V_a = 55 ml

Initial molarity; M_a = 3 M

Molarity of desired solution; M_b = 0.75 M

Volume of desired solution; V_b = (55 + x) ml

Where x is the volume of water to be added.

To solve for V_b, we will use the equation ;

M_a•V_a = M_b•V_b

V_b = (M_a•V_a)/M_b

V_b = (3 × 55)/0.75

V_b = 220 mL

Thus;

(55 + x) = 220

x = 220 - 55

x = 165 mL

User Sparkup
by
2.8k points