Final answer:
Reaction 1, NH₃ + HCl ⟼ NH₄Cl, is a synthesis reaction because two reactants form a single product, making option (c) the most accurate. Reaction 2, Ca (OH)₂ + 2 HCl ⟼ CaCl₂ + 2 H₂O, is not a synthesis reaction but an acid-base reaction, making options (a) and (b) incorrect.
Step-by-step explanation:
The question involves identifying synthesis reactions in a set of given chemical reactions. A synthesis reaction is characterized by multiple reactants combining to form a single product. In the cases presented:
- Reaction 1: NH₃ (aq) + HCl (aq) ⟼ NH₄Cl (aq)
- Reaction 2: Ca (OH)₂ (s) + 2 HCl (aq) ⟼ CaCl₂ (aq) + 2 H₂O (l)
In Reaction 1, ammonia and hydrochloric acid combine to form ammonium chloride, making this reaction a synthesis reaction as there is only one product formed. Therefore, statements (c) Reaction 1 is a synthesis reaction because there is only 1 product and (d) Reaction 1 is a synthesis reaction because there are 2 reactants in the equation are correct. However, the defining characteristic of a synthesis reaction is the formation of a single product from multiple reactants, making (c) the most accurate reason for Reaction 1 being a synthesis reaction.
Reaction 2 is not a synthesis reaction since it produces two products, calcium chloride and water, and is instead an example of an acid-base neutralization reaction. Therefore, statements (a) and (b) are incorrect.