Question

Malachite green is a toxic chemical, contains C, H, Cl, and N. If a solution of malachite green dye is 0.00500% by mass, and malachite green has the formula C23H25ClN2, what is the molarity of the solution? Assume the solution is dilute enough that its density is the same as that of water (1.00 g/mL).

Answer 1

0.0136 M

Step-by-step explanation:

To calculate the molarity of the solution, you need to know the number of moles of malachite green dye present in the solution.

First, convert the mass percentage of the solution to grams. If the solution is 0.00500% by mass, and the density of the solution is 1.00 g/mL, then 0.00500 g of malachite green dye is present in every 100mL of solution.

Next, use the molar mass of malachite green dye to convert the mass of the solution to moles. The molar mass of C23H25ClN2 is calculated as:

Molar mass = (23 x 12.01) + (25 x 1.01) + (35.5) + (14.01) = 368.74g/mol

Therefore, the number of moles of malachite green dye in 0.00500g is:

0.00500g / 368.74g/mol = 1.36x10^-4 mol

Now you can calculate the molarity using the following formula:

Molarity = moles of solute/ liters of solution

1.36x10^-4 mol / 0.1 L = 0.0136 M

So the molarity of the solution is 0.0136 M