Question

A solution has a molaity of 4.5 M. It needs to be diluted to fom 1.75 L of a 0.5 M solution. How much of the 4.5 M solution is needed?

Answer 1

To calculate the amount of the 4.5 M solution needed to make a 0.5 M solution, we can use the formula:

C1V1 = C2V2

Where C1 is the initial concentration, V1 is the initial volume, C2 is the final concentration, and V2 is the final volume.

Let's plug in the values given in the problem:

C1 = 4.5 M

C2 = 0.5 M

V2 = 1.75 L

We can solve for V1 to find the initial volume of the 4.5 M solution needed:

V1 = (C2V2) / C1

V1 = (0.5 M)(1.75 L) / 4.5 M

V1 = 0.194 L

Therefore, you would need to measure out 0.194 L (or 194 mL) of the 4.5 M solution and add enough solvent (such as water) to make a final volume of 1.75 L to get a 0.5 M solution.