When equal volume of 1M HCl and 1M H$_2$SO$_4$ are separately neutralized by excess volume of 1M NaOH solution, X and Y kJ of heat is liberated respectively. The value of Y/X is ____.
Correct Answer: 2
Approach Solution - 1
To solve the problem, we must first understand the concept of neutralization enthalpy. When a strong acid is neutralized by a strong base, the reaction releases heat. The standard enthalpy change for neutralization of a strong acid by a strong base is approximately 57 kJ/mol.
Consider the reactions:
1. For HCl: HCl(aq) + NaOH(aq) -> NaCl(aq) + H2O(l)
2. For H2SO4: H2SO4(aq) + 2NaOH(aq) -> Na2SO4(aq) + 2H2O(l)
In the first reaction, 1 mole of HCl neutralizes 1 mole of NaOH. Since 1M HCl is used, and mixed in equal volume with NaOH, 1 mole of NaOH will react, releasing 57 kJ of heat per mole. Thus, X = 57 kJ.
In the second reaction, 1 mole of H2SO4 neutralizes 2 moles of NaOH. Hence, for 1 mole of H2SO4 mixed with NaOH, 2 moles of NaOH react, liberating 57 kJ × 2 = 114 kJ of heat. Therefore, Y = 114 kJ.
The ratio of heat liberated Y/X = 114/57 = 2.
This value, 2, matches the expected range of (2,2), confirming our solution's consistency and correctness.
Approach Solution -2
Neutralization reactions:
\( \mathrm{H^+ + OH^- \rightarrow H_2O} \quad (\text{from HCl: } X), \)
\( \mathrm{2H^+ + 2OH^- \rightarrow 2H_2O} \quad (\text{from } H_2SO_4: Y). \)
From the reactions:
\( Y = 2X \implies \frac{Y}{X} = 2. \)
Final Answer: 2.
Top JEE Main Chemistry Questions
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)- At equilibrium the concentrations of and in a sealed vessel at . What will be for the reaction
- Find out the major products from the following reactions
Cobalt chloride when dissolved in water forms pink colored complex $X$ which has octahedral geometry. This solution on treating with cone $HCl$ forms deep blue complex, $\underline{Y}$ which has a $\underline{Z}$ geometry $X, Y$ and $Z$, respectively, are
- The correct order of atomic radii is:
Top JEE Main Enthalpy change Questions
- Decreasing order of electron gain enthalpy of the following elements (magnitude only)
Sulphur A, Bromine - B, Fluorine C, Argon D 
If standard enthalpy of vaporization of \(CCl_4\) is \(30.5\) kJ/mol, find heat absorbed for vaporization of \(294 \) gm of \(CCl_4\). [Nearest integer] [in kJ/mol]
- $\text{Standard enthalpy of vaporisation for CCl}_4 \text{ is 30.5 kJ mol}^{-1}. \text{ Heat required for vaporisation of } 284 \, \text{g of CCl}_4 \text{ at constant temperature is } \_\_\_\_ \, \text{kJ.} \\ \text{(Given molar mass in g mol}^{-1}\text{; C = 12, Cl = 35.5)}$
- $\text{Two reactions are given below:}$ \[ 2\text{Fe}_{(s)} + \frac{3}{2}\text{O}_{2(g)} \rightarrow \text{Fe}_2\text{O}_{3(s)}, \Delta H^\circ = -822 \, \text{kJ/mol} \] \[ \text{C}_{(s)} + \frac{1}{2}\text{O}_{2(g)} \rightarrow \text{CO}_{(g)}, \Delta H^\circ = -110 \, \text{kJ/mol} \] $\text{Then enthalpy change for the following reaction}$ \[ 3\text{C}_{(s)} + \text{Fe}_2\text{O}_{3(s)} \rightarrow 2\text{Fe}_{(s)} + 3\text{CO}_{(g)} \]
Top JEE Main Questions
- Two masses $m$ and $\frac{m}{2}$ are connected at the two ends of a massless rigid rod of length $l$. The rod is suspended by a thin wire of torsional constant $k$ at the centre of mass of the rod-mass system(see figure). Because of torsional constant $k$, the restoring torque is $\tau =k\theta$ for angular displacement $\theta$. If the rod is rota ted by $\theta_0$ and released, the tension in it when it passes through its mean position will be:
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)- The value of is
- The number of terms of an is even. The sum of the odd terms is and of the even terms is . The last term exceeds the first by . Then the number of terms in the series is ______.
A black body is at a temperature of 2880 K. The energy of radiation emitted by this body with wavelength between 499 nm and 500 nm is U1, between 999 nm and 1000 nm is U2 and between 1499 nm and 1500 nm is U3. The Wien's constant, b = 2.88×106 nm-K. Then,