# Calculate the mass of the precipitate that will precipitate when an excess of potassium carbonate interacts with 31.4 g

Calculate the mass of the precipitate that will precipitate when an excess of potassium carbonate interacts with 31.4 g of a barium nitrate solution with a mass fraction of the latter of 10%. 1) Let’s compose the reaction equation:
K2CO3 + Ba (NO3) 2 = BaCO3 ↓ + 2KNO3
2) Calculate the mass and amount of the barium nitrate substance in the solution:
m (Ba (NO3) 2) = (m (solution) ∙ ω) / 100% = (31.4 ∙ 10) / 100 = 3.14 g.
n (Ba (NO3) 2) = m (Ba (NO3) 2) / M (Ba (NO3) 2) = 3.14 / 261 = 0.012 mol.
3) Determine the mass of the precipitated substance:
according to the reaction equation
n (BaCO3) = n (Ba (NO3) 2) = 0.012 mol;
m (BaCO3) = n (BaCO3) ∙ M (BaCO3) = 0.012 ∙ 197 = 2.36 g. Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.