what volume (in l) of a 1.25 m
potassium fluoride (kf) solution
would be needed to make 455 ml of
a 0.838 m solution by dilution?
[? ]lkf

V1= 0.305L

Explanation:

To find the initial volume of 1.25M potassium fluoride needed to make tge dilution specified in the question, we can use: C1 × V1 = C2 × V2

Since the question wants the volume in litres, convert 455 mL to L

455/ 1000

= 0.455 L

Now make the substitution

1.25 × V1 = 0.838 × 0.455

Rearrange to make V1 the subject

V1=

"record the time to complete a chemical reaction" would most likely be part of a lab procedure.