An excess of calcium nitrate solution was added to a solution of potassium carbonate weighing 27.6

| May 2, 2021 | education

An excess of calcium nitrate solution was added to a solution of potassium carbonate weighing 27.6 g and a mass fraction of 20%. Calculate the mass of the precipitate formed.

K2CO3 + Ca (NO3) 2 = 2KNO3 + CaCO3.
1) Find the mass of the solute potassium carbonate. To do this, we multiply the mass fraction of the substance by the mass of the solution and divide by one hundred percent: 20 * 27.6 / 100 = 5.52 g.
2) Find the molar mass of potassium carbonate according to the periodic table: 2 * 39 + 12 + 3 * 16 = 138.
3) Find the amount of potassium carbonate substance. To do this, divide its mass by its molar mass: 5.52 / 138 = 0.04 mol.
4) According to the reaction equation, there is one mole of calcium carbonate (precipitate) per mole of potassium carbonate. This means that the amount of calcium carbonate substance is 0.04 mol.
5) Sludge mass: 0.04 * 100 = 4g – answer.



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.