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.
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.
Correct Answer: 4
Solution and Explanation
(A) I$_2$ (g) $\rightarrow$ 2I (g) is an endothermic process (Atomisation).
(B) HCl (g) $\rightarrow$ H (g) + Cl (g) is an endothermic process (Atomisation).
(C) H$_2$O (l) $\rightarrow$ H$_2$O (g) is an endothermic process (Vaporisation).
(D) C (s) + O$_2$ (g) $\rightarrow$ CO$_2$ (g) is an exothermic process (Combustion).
(E) Dissolution of ammonium chloride in water is an endothermic process (Dissolution).
Thus, the number of endothermic processes is 4.
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