Question

How many milliliters of 2.55M NaOH is needed to make 125mL of 0.75M NaOH solution??

Answer 1

Answer:

36.7 milliliters of 2.55M NaOH will be needed

Explanation:

Molarity of NaOH solution = $M_1=2.55 M$

$V_1=?$

Molarity of 125 mL NaOH solution  = $M_2=0.75 M$

$V_2=125 mL = 0.125 L$

Using dilution formula :

$M_1V_1=M_2V_2$

$2.55 M \times V_1=0.75 M\times 0.125 L$

$V_1=0.0367 L = 36.7 mL$

36.7 milliliters of 2.55M NaOH will be needed

Answer 2

As i am reading the problem, i notice they give two concentrations (M), a volume and asking for the other volume; this should be a hint that we need to use the dilution formula---> M1V1 = M2V2

M1= 2.55 M
V1= ?
M2= 0.75 M
V2= 125 mL

now, we plug in the values into the formula

(2.55 x V1) = (0.75 x 125)

V1= 36.8 mL