Question

What is the concentration of Iodine I2 molecules in a solution containing 2.54 g of iodine 250 cm3 of solution? A 0.01mol/dm3 B 0.02mol/dm3 C 0.04mol/dm3 D 0.08mol/dm3

Answer 1

C. 0.04 moles per cubic decimeter.

Step-by-step explanation:

The molar mass of the Iodine is 253.809 grams per mole and a cubic decimeter equals 1000 cubic centimeters. The concentration of Iodine (
`c`), measured in moles per cubic decimeter, can be determined by the following formula:

`c = (m)/(M\cdot V)` (1)

Where:

`m` - Mass of iodine, measured in grams.

`M` - Molar mass of iodine, measured in grams per mol.

`V` - Volume of solution, measured in cubic decimeters.

If we know that
`m = 2.54\,g`,
`M = 253.809\,(g)/(mol)` and
`V = 0.25\,dm^(3)`, then the concentration of iodine in a solution is:

`c = (2.54\,g)/(\left(253.809\,(g)/(mol) \right)\cdot (0.25\,dm^(3)))`

`c = 0.04\,(mol)/(dm^(3))`

Hence, the correct answer is C.