Question

Определите массу оксида фосфора(V) и воды для получения 400гр раствора оркофосфорной кислоты массовая доля 2%

Answer 1

P2O5+3H2O====2H3PO4

НАЙДЕМ МАССУ H3PO4=400*0,02=8г

теперь массу воды Х----------8

                                     54---------196

Х=2,2г воды

 

найдем массу P2O5

Х----------8г

142-------196

х=5,8г P2O5

Answer 2

Calculating the Mass of Phosphorus(V) Oxide and Water

To determine the mass of phosphorus(V) oxide and water needed to obtain 400g of a solution of orthophosphoric acid with a mass fraction of 2%, we can follow these steps:

1. Calculate the Mass of Orthophosphoric Acid: - The mass fraction of the orthophosphoric acid is given as 2%. This means that in 400g of the solution, the mass of the acid is 2% of 400g. - Therefore, the mass of orthophosphoric acid in the solution is 2% of 400g, which is 8g.

2. Determine the Composition of Orthophosphoric Acid: - Orthophosphoric acid has the chemical formula H3PO4. This means that it contains phosphorus(V) oxide (P2O5) and water (H2O). - The molar mass of P2O5 is 141.94 g/mol, and the molar mass of H2O is 18.02 g/mol.

3. Calculate the Mass of Phosphorus(V) Oxide and Water: - The molar ratio of P2O5 to H2O in H3PO4 is 2:3. This means that for every 2 moles of P2O5, there are 3 moles of H2O. - Using the molar masses, we can calculate the mass of P2O5 and H2O needed to obtain 8g of orthophosphoric acid.

4. Perform the Calculations: - Let's calculate the mass of P2O5 and H2O required based on the molar ratio and the mass of orthophosphoric acid.

5. Conclusion: - By following these steps, we can determine the mass of phosphorus(V) oxide and water required to obtain 400g of a solution of orthophosphoric acid with a mass fraction of 2%.

Let's proceed with the calculations to determine the mass of phosphorus(V) oxide and water needed.