Question

A student wants to make 135. mL of 8.5 M KBr by diluting a 6.0 M KBr solution. How much of that solution should be used?

Answer 1

`V = 101.25` `mL` from concentrated solution

Explanation:

Using the dilution equation:

`(V M)_1 = (V M)_2`

Where
V: volume (L)
M: molarity (mol/L)

So, substituting data in previous equation

`(V` x `8.5 "mol"/L)_1 = (0.135 L` x `6"mol"/L)_2`

Solving

`V = 0.10125` `L`

Or,

`V = 101.25` `mL` from concentrated solution