Question

В 100г 9,8%-ного раствора фосфорной кислоты растворили 14,2 г оксида фосфора(5) массовая доля фосфорной кислоты в полученном растворе?

Answer 1

Держи, если что - спрашивай

Answer 2

Calculating the Mass Fraction of Phosphoric Acid in the Solution

To calculate the mass fraction of phosphoric acid in the solution, we can use the given information about the concentration of the phosphoric acid solution and the mass of phosphorus pentoxide (P2O5) dissolved in it.

Given: - Mass of 9.8% phosphoric acid solution = 100g - Mass of phosphorus pentoxide (P2O5) dissolved = 14.2g

Calculation Steps:

1. Calculate the mass of phosphoric acid in the solution: - The molar mass of P2O5 is 141.94 g/mol, and the molar mass of H3PO4 (phosphoric acid) is 98.00 g/mol. - Using the molar ratio of P2O5 to H3PO4 (1:2), we can calculate the mass of H3PO4 present in the solution.

The mass of H3PO4 = (mass of P2O5) * (molar mass of H3PO4 / molar mass of P2O5)

   mass of H3PO4 = 14.2g * (98.00g/mol / 141.94g/mol) = 9.84g
   

2. Calculate the mass fraction of phosphoric acid: - The mass fraction of phosphoric acid is the ratio of the mass of H3PO4 to the total mass of the solution.

Mass fraction of H3PO4 = (mass of H3PO4) / (total mass of solution)

   mass fraction of H3PO4 = 9.84g / 100g = 0.0984 or 9.84%
   

Answer:

The mass fraction of phosphoric acid in the obtained solution is approximately 9.84%.