Answer:
Cl2 concentration: 1,048 ppm
Explanation:
Molarity (M) is a unit that indicates how many moles of a substance are in one liter of solution, while ppm is similar to mg/L, representing the mass of the substance per liter. To convert M to ppm, we need to consider both mass and volume. The volume remains in liters in both cases, so no adjustments are needed there. The challenge arises when converting moles from molarity to milligrams for the mg/L conversion to find ppm.
First, we must recognize that the substance in question is Cl2, prompting the need to connect mole quantity to its mass. Referring to the periodic table, we find the atomic weight of Cl is 35.4 g/mole. This relationship allows us to establish moles' mass, as shown in the following equation:

We already know the moles of Cl2 in the solution is (moles=2.96x10^-5). Substituting this value, we can calculate:

Keep in mind that we're discussing the mass found per liter of solution, which gives us 1.048x10^-3 g/L. We previously established that ppm equals mg/L, so we need to convert grams to milligrams:
1 g = 1000 mg
Now multiplying both sides by 1.048x10^-3:
1 * 1.048x10^-3 g = 1000 * 1.048x10^-3 mg
Thus, 1,048x10^-3 g translates to 1,048 mg.
This amount of mass detected in one liter indicates that the concentration of the substance in the solution is:
1,048 mg/L
Since we know that mg/L=ppm, the conclusion is:
1,048 ppm