Calculate the mass of phosphorus that can be obtained by reducing 77.5 kg of calcium phosphate containing 20% impurities with coal.

| February 23, 2021 | education

First, let’s write the reaction equation. To obtain phosphorus from calcium phosphate, coal and sand (silicon oxide) are used, heating this mixture at a high temperature:
2Cа3 (PO4) 2 + 10C + 6 SiO2 = 6Ca2SiO3 + 10 CO + 4P
Now let’s calculate the mass of pure calcium phosphate, without impurities:
m (Ca3 (PO4) 2) = total m * W = 77.5 * 0.8 = 62 kg
where w is the mass fraction of calcium phosphate, which was calculated as follows:
w = 100 – 20 = 80% or 0.8
Then we calculate the molar mass of calcium phosphate
M (Ca3 (PO4) 2) = 3 * 40 + 2 * 31 + 8 * 16 = 120 + 62 + 128 = 310 g / mol
And now, based on the reaction equation, let’s make the proportion:
62 / (2 * 310) = x / 4 * 31, whence X = 7688/620 = 12.4 kg
where X is the required mass of phosphorus
Answer: the mass of the released phosphorus is 12.4 kg.



One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.