Express the concentration of a 0.0350 m aqueous solution of fluoride, f − , in mass percentage and in parts per million (ppm). assume the density of the solution is 1.00 g/ml. a. number in percentage %
b. number in ppm .

Answer :

(a) The mass percentage is 0.0665 %

(b) The concentration in ppm is 665 ppm.

Explanation :

Part (a) :

As we are given that, 0.0350 M aqueous solution of fluoride ion that means 0.0350 moles of fluoride ion present in 1 L of solution.

First we have to calculate the mass of fluoride ion.

Molar mass of = 19 g/mole

Now we have to calculate the mass of solution.

Mass of solution = Density of solution × Volume of solution

Density of solution = 1.00 g/mL

Volume of solution = 1 L = 1000 mL

Mass of solution = 1.00 g/mL × 1000 mL

Mass of solution = 1000 g

Now we have to calculate the mass -percentage.

Thus, the mass percentage is 0.0665 %

Part (b) :

Parts per million (ppm) : It is defined as the mass of a solute present in one million parts by the mass of the solution.

Now we have to calculate the concentration in ppm.

Thus, the concentration in ppm is 665 ppm.

chemists can use the electron cloud model to assign electrons to different atomic orbitals. atomic orbitals also explain the patterns in the periodic table

explanation:

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.