20. Solving a chemistry problem

68. The most effective way to neutralize contaminated wastewater from chemical enterprises is to treat them with substances that precipitate harmful impurities in the form of sparingly soluble compounds. At the same time, it is important that the precipitant be in excess, since otherwise, obviously, the required degree of wastewater treatment will not be achieved. The enterprise supplies wastewater containing 3.31 kg of lead(II) nitrate to the water treatment site. Lead (II) cations are precipitated by adding 1.27 kg of sodium carbonate to the solution. Determine which reagent and in what quantity is in excess. Calculate also the mass of precipitated lead (II) carbonate.