The number of endothermic process/es from the following is _____ . A. \(I_2 (g) → 2I (g)\) B. \(HCl (g) → H(g) + Cl (g)\) C. \(H_2O(l) → H_2O (g)\) D. \(C(s) + O_2 (g) → CO_2 (g)\) E. Dissolution of ammonium chloride in water.
To determine the number of endothermic processes, we must assess each provided reaction and process. Endothermic reactions absorb energy from the surroundings, usually indicated by the input of heat.
Process Analysis:
\(I_2 (g) → 2I (g)\): This is bond dissociation, an endothermic process as energy is required to break the bond.
\(HCl (g) → H(g) + Cl (g)\): Bond breaking occurs, which is endothermic due to the energy needed to separate the atoms.
\(H_2O(l) → H_2O (g)\): Vaporization occurs here, requiring energy input to overcome intermolecular forces in liquid water to change it into gas, making it endothermic.
\(C(s) + O_2 (g) → CO_2 (g)\): This is a combustion reaction, which is exothermic as it releases energy.
Dissolution of ammonium chloride in water: This process is endothermic because it absorbs heat, causing a cooling effect.
Thus, the endothermic processes are A, B, C, and E. The number of endothermic processes is 4.
Verification: The computed value 4 matches the expected range of 4, 4.
