In an exothermic reaction, heat is evolved, and system loses heat to the surrounding. For such system
(a) $q_{p}$ will be negative
(b) $Δ_{r} H$ will be negative
(c) $q_{p}$ will be positive
(d) $Δ_{r} H$ will be positive

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Solution

(b)

Exothermic reactions are those reactions which are accompanied by the evolution of heat.
e.g., $C (s) + O_{2} (g) \to C O_{2} (g) + 393.5 k J$
$H_{2} (g) + \frac{1}{2} O_{2} (g) \to H_{2} O (l) + 285.8 k J$
$q_{p}$ and $Δ_{r} H$ are negative for exothermic reaction.

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In an exothermic reaction, heat is evolved, and system loses heat to the surrounding. For such system (a) qp will be negative (b) ΔrH will be negative (c) qp will be positive (d) ΔrH will be positive

(b) Exothermic reactions are those reactions which are accompanied by the evolution of heat. e.g., C(s)+O2(g)→CO2(g)+393.5 kJ H2(g)+12O2(g)→H2O(l)+285.8 kJ qp and ΔrH are negative for exothermic reaction.

In an exothermic reaction, heat is evolved, and system loses heat to the surrounding. For such system
(a) $q_{p}$ will be negative
(b) $Δ_{r} H$ will be negative
(c) $q_{p}$ will be positive
(d) $Δ_{r} H$ will be positive

(b)

Exothermic reactions are those reactions which are accompanied by the evolution of heat.
e.g., $C (s) + O_{2} (g) \to C O_{2} (g) + 393.5 k J$
$H_{2} (g) + \frac{1}{2} O_{2} (g) \to H_{2} O (l) + 285.8 k J$
$q_{p}$ and $Δ_{r} H$ are negative for exothermic reaction.