MCQ
For conversion $C$ (graphite) $→ C$ (diamond) the $\Delta S$ is
- AZero
- BPositive
- ✓Negative
- DUnknown
✓
Answer
Correct option: C.
Negative
(c)Conversion of graphite into diamond is an endothermic reaction. So, heat of diamond is higher than that of graphite. But $\Delta S$would be negative for the conversion of graphite into diamond.
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
Which of the following does not show geometrical isomerism ?
$2\,L$ of $0.2\,M H _{2} SO _{4}$ is reacted with $2\,L$ of $0.1\,M$ $NaOH$ solution, the molarity of the resulting product $Na _{2} SO _{4}$ in the solution is millimolar. (Nearest integer).
→Given below are two statements:
→Statement $(I)$ : Fusion of $\mathrm{MnO}_2$ with $\mathrm{KOH}$ and an oxidising agent gives dark green $\mathrm{K}_2 \mathrm{MnO}_4$.
Statement $(II)$ : Manganate ion on electrolytic oxidation in alkaline medium gives permanganate ion.
In the light of the above statements, choose the correct answer from the options given below.
Carbolic acid is
According to $VSEPR$ theory
→The final product $\mathrm{A}$, formed in the following reaction sequence is:
→$\mathrm{Ph}-\mathrm{CH}=\mathrm{CH}_2 \xrightarrow[\text { (iii) } \mathrm{HBr}{(iv) \mathrm{Mg}, ether, then \mathrm{HCHO} / \mathrm{H}_3 \mathrm{O}^{+}}]{{(i)BH_3}{\text { (ii) } \mathrm{H}_2 \mathrm{O}_2,{ }^{\text {(-) }} \mathrm{OH}}} \mathrm{A}$
Order of acidic nature
A metal surface is exposed to $500\, \mathrm{~nm}$ radiation. The threshold frequency of the metal for photoelectric current is $4.3 \times 10^{14}\, \mathrm{~Hz}$. The velocity of ejected electron is $.......\,\times 10^{5} \mathrm{~ms}^{-1}$ (Nearest integer)
→[Use : $\left.\mathrm{h}=6.63 \times 10^{-34}\, \mathrm{Js}, \mathrm{m}_{\mathrm{e}}=9.0 \times 10^{-31}\, \mathrm{~kg}\right]$
The table shown below gives the bond dissociation energies $({E_{diss}})$ for single covalent bonds of carbon $(C)$ atoms with element $A,\,\,B,\,\,C$ and $D.$ Which element has the smallest atoms
→| $Bond$ | $E_{(diss)}(kJ(mol )^{(-1)})$ |
| $C-A$ | $240$ |
| $C-B$ | $328$ |
| $C-C$ | $276$ |
| $C-D$ | $485$ |
In a saturated solution of electrolyte, the ionic product of their concentration are constant at constant temperature and this constant for electrolyte is known as