MCQ
$\Delta U^{\theta}$ of combustion of methane is $-X \,kJ \,mol ^{-1}.$ The value of $\Delta H^{\theta}$ is
- A$=\Delta U^{\theta}$
- ✓$\,<\,\Delta U^{\theta}$
- C$\,>\,\Delta U^{\theta}$
- D$=0$
✓
Answer
Correct option: B.
$\,<\,\Delta U^{\theta}$
b
Since $\Delta H^{\theta}=\Delta U^{\theta}+\Delta n_{g} R T$ and $\Delta U^{\theta}=-X \,k J\, mol ^{-1}$
Since $\Delta H^{\theta}=\Delta U^{\theta}+\Delta n_{g} R T$ and $\Delta U^{\theta}=-X \,k J\, mol ^{-1}$
$\Delta H^{\theta}=(-X)+\Delta n_{g} R T, \Rightarrow \Delta H^{\theta}\,<\,\Delta U^{\theta}$
Therefore, alternative $(ii)$ is correct.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
The difference between bond orders of $\mathrm{CO}$ and $\mathrm{NO}$ is $\mathrm{NO}^{\oplus}$ is $\frac{\mathrm{x}}{2}$ where $\mathrm{x}=.....$
→(Round off to the Nearest Integer)
Which of the following cation can not give borax bead test ?
How many degrees of unsaturation are there the following compound ?
In the long form of the periodic table, all the non- metals are placed under
The solubility product of a sparingly soluble salt $AB$ at room temperature is $1.21 \times 10^{-6},$ its molar solubility is :
→The uncertainty in the position of an electron $($ mass = $9.1 \times {10^{ - 28}}$ $g)$ moving with a velocity of $3.0 \times {10^4}\,cm\,{s^{ - 1}}$ accurate upto $0.001\%$ will be ................. $\mathrm{cm}$ (Use$\frac{h}{{4\pi }}$ in the uncertainty expression, where $h = 6.626 \times {10^{ - 27}}\,erg - s$)
→The spin only magnetic moment of a divalent ion in aqueous solution (atomic number 29$)$ is ...... $BM.$
→Which one of the following statements is/ are incorrect regarding photochemical smog?
During a chemical reaction with water, alkali metal oxide and halogen oxide behave respectively as :
The energy required to dislodge electron from excited isolated H-atom, $I{E_1} = 13.6\,\,eV$ is
→