Question

Fe + CuSO4(p-p) = Сu + FeSO4(p-p). Что означает "(p-p)"?

Answer 1

"Р-р" эт коротко слово "раствор", т.е раствор соли

Answer 2

"(p-p)" in the chemical equation you provided stands for "precipitate." When a chemical reaction produces a solid that is insoluble in the reaction mixture, it forms a precipitate. In this context, it means that the reaction between iron (Fe) and copper(II) sulfate (CuSO4) produces solid copper (Cu) and solid iron(II) sulfate (FeSO4) as the products. The precipitate will appear as a solid substance that falls out of the solution and settles at the bottom of the container.