What volume of (dm\(^3\)) of water will be added to 10dm\(^3\) of 2.0 mol/dm\(^3\) HCL acid solution to give a final solution of 0.5 mol/dm\(^3\)?
A
30
B
40
C
20
D
50
Verified Correct Answer: A.
Step-by-Step Mathematical Solution
To make a fixed amount of a dilute solution from a stock solution,
use the formula: C\(_1\)V\(_1\) = C\(_2\)V\(_2\)
where: V\(_1\) = Volume of stock solution needed to make the new solution.
C\(_1\) = Concentration of stock solution.
V\(_2\) = Final volume of new solution.
C\(_2\)= Final concentration of stock solution
2 * 10 = 0.5 * V2
20 = 0.5V2
\(\frac{20}{0.5}\) = V2
V\(_2\)= 40dm\(^3\)
What would be added = V\(_2\) - V\(_1\)
= 40 - 10 = 30dm\(^3\)
Source: WAEC / JAMB / NECO Classroom Archive (Record #65039)