Equal volumes of molar hydrochloric acid and sulphuric acid are neutralised by dilute NaOH solution and x kcal and y kcal of heat are liberated respectively. Which of the following is true?

Question

Equal volumes of molar hydrochloric acid and sulphuric acid are neutralised by dilute NaOH solution and x kcal and y kcal of heat are liberated respectively. Which of the following is true? (A) x = y (B) x=(y/2) (C) x = 2y (D) none of the above

Tardigrade Admin · Accepted Answer

Heat of neutralisation = Heat of formation of water (1 mol)

H Cl + N a O H ⟶ N a Cl + H_{2} O; Δ H = - x

or

1 m o l H^{+} + 1 m o l O H^{-} ⟶ 1 m o l H_{2} O;

Δ H = x

H_{2} S O_{4} + 2 N a O H \to N a_{2} S O_{4} + 2 H_{2} O; Δ H = - y

or

2 H^{+} + 2 O H^{-} ⟶ 2 H_{2} O; Δ H = - y

H^{+} + O H^{-} ⟶ H_{2} O; Δ H = - \frac{y}{2}

\Rightarrow Δ H = Δ H

∴ x = \frac{y}{2}

Q. Equal volumes of molar hydrochloric acid and sulphuric acid are neutralised by dilute $N a O H$ solution and $x$ kcal and $y$ kcal of heat are liberated respectively. Which of the following is true?

$x = y$

$x = \frac{y}{2}$

$x = 2 y$

none of the above

Q. Equal volumes of molar hydrochloric acid and sulphuric acid are neutralised by dilute NaOH solution and x kcal and y kcal of heat are liberated respectively. Which of the following is true?

x=y

x=2y​

x=2y

none of the above

Heat of neutralisation = Heat of formation of water (1 mol) HCl+NaOH⟶NaCl+H2​O;ΔH=−x or 1molH​++1molOH−​⟶1molH2​O​; ΔH=x H2​SO4​+2NaOH→Na2​SO4​+2H2​O;ΔH=−y or 2H++2OH−⟶2H2​O;ΔH=−y H++OH−⟶H2​O;ΔH=−2y​ ⇒ΔH=ΔH ∴x=2y​

Q. Equal volumes of molar hydrochloric acid and sulphuric acid are neutralised by dilute $N a O H$ solution and $x$ kcal and $y$ kcal of heat are liberated respectively. Which of the following is true?

$x = y$

$x = \frac{y}{2}$

$x = 2 y$