Task: Question Answering
Input (English): Question: Among the partial reactions that lead to sodium carbonate by the Solvay Process, are: 
 Options:  <1> The reaction between calcium carbonate and sodium chloride. <2> The precipitation of sodium hydrogen carbonate. <3> The thermal decomposition of ammonium chloride. <4> The formation of CaCO3 from CaO and CO2. <5> The reaction of ammonia with calcium oxide.
Output (English): 2