# Calculate the mass of the sediment which is formed by 305 g of sodium silicate with a yield of 98%.

Let’s implement the solution:

1. Let us write down the equation according to the problem statement:

Na2SiO3 + 2HCl = H2SiO3 + 2NaCl – ion exchange reaction, obtained silicic acid in the precipitate;

2. Calculations by formulas:

M (Na2SiO3) = 121.8 g / mol;

M (H2SiO3) = 78 g / mol.

3. Determine the number of moles of sodium silicate, if the mass is known:

Y (Na2SiO3) = m / M = 305 / 121.8 = 2.5 mol;

Y (H2SiO3) = 2.5 mol since the amount of these substances according to the equation is equal to 1 mol.

4. Find the theoretical mass for the product:

m (theoretical) = Y * M = 2.5 * 78 = 195 g;

W = m (practical) / m (theoretical) * 100;

m (practical) H2SiO3 = 0.98 * 195 = 191.1 g.

Answer: during the reaction, silicic acid with a mass of 191.1 g was obtained.