The total number of possible isomers for $\left[\mathrm{Pt}{\left({\mathrm{NH}}_3\right)}_4{\mathrm{Cl}}_2\right]{\mathrm{Br}}_2$ is___.

The work function ( \(\Phi\) ) of some metals is listed below. The number of metals which will show photoelectric effect when light of \(300 \mathrm{~nm}\) wavelength falls on the metal is

For a first order reaction, \(A \rightarrow P\), the temperature \((T)\) dependent rate constant \((k)\) was found to follow the equation, \(\log k=-(2000) / T+6.0\)
The pre-exponential factor \(A\) and the activation energy \(\left(E_a\right)\), respectively, are

Complete reaction of acetaldehyde with excess formaldehyde, upon heating with conc. \(\mathrm{NaOH}\) solution, gives \(\mathbf{P}\) and \(\mathbf{Q}\). Compound \(\mathbf{P}\) does not give Tollens' test, whereas \(\mathbf{Q}\) on acidification gives positive Tollens' test. Treatment of \(\mathbf{P}\) with excess cyclohexanone in the presence of catalytic amount of \(p\)-toluenesulfonic acid (PTSA) gives product \(\mathbf{R}\).
Sum of the number of methylene groups \(\left(-\mathrm{CH}_2-\right)\) and oxygen atoms in \(\mathbf{R}\) is ________.

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The noble gases have closed-shell electronic configuration and are monoatomic gases under normal conditions. The low boiling points of the lighter noble gases are due to weak dispersion forces between the atoms and the absence of other interatomic interactions.
The direct reaction of xenon with fluorine leads to a series of compounds with oxidation numbers \(+2,+4\) and \(+6 . \mathrm{XeF}_4\) reacts violently with water to give \(\mathrm{XeO}_3\). The compounds of xenon exhibit rich stereochemistry and their geometries can be deduced considering the total number of electron pairs in the valence shell.
Question:
The structure of \(\mathrm{XeO}_3\) is

At room temperature, disproportionation of an aqueous solution of in situ generated nitrous acid \(\left(\mathrm{HNO}_2\right)\) gives the species

Match the orbital overlap figures shown in List-I with the description given in List-II and select the correct
answer using the code given below the lists.

	List – I		List - II
A.		P	$\mathrm{p}-\mathrm{d}\mathrm{}\mathrm{\pi }$ antibonding
B.		Q	$\mathrm{d}-\mathrm{d}\mathrm{}\mathrm{\sigma }$ bonding
C.		R	$\mathrm{p}-\mathrm{d}\mathrm{}\mathrm{\pi }$ bonding
D.		S	$\mathrm{d}-\mathrm{d}\mathrm{}\mathrm{\sigma }$ antibonding

Four persons independently solve a certain problem correctly with probabilities $\frac{1}{2},\frac{3}{4},\frac{1}{4},\frac{1}{8}$. Then the probability that the problem is solved correctly by at least one of them is

Consider the equation ${\int }_1^e\frac{{\left({\log }_{e}x\right)}^{{\displaystyle \frac{1}{2}}}}{x{\left(a-{\left({\log }_{e}x\right)}^{{\displaystyle \frac{3}{2}}}\right)}^2}dx=1,a\in \left(-\infty ,0\right)\cup \left(1,\infty \right)$. Which of the following statements is/are TRUE?

A horizontal stretched string, fixed at two ends, is vibrating in its fifth harmonic according to the equation, \(y ( x , t )=(0.01 m) \sin \left[\left(62.8 m^{-1}\right) x \right]\) \(\cos \left[\left(628 s^{-1}\right) t \right]\). Assuming \(\pi=3.14\), the correct statement(s) is (are)

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In hexagonal system of crystals, a frequently encountered arrangement of atoms is described as a hexagonal prism. Here, the top and bottom of the cell are regular hexagons and three atoms are sandwiched in between them. A space-filling model of this structure, called hexagonal close-packed (HCP), is constituted of a sphere on a flat surface surrounded in the same plane by six identical spheres as closely as possible. Three spheres are then placed over the first layer so that they touch each other and represent the second layer. Each one of the three spheres touches three spheres of the bottom layer. Finally, the second layer is covered with a third layer that is identical to the bottom layer in relative position. Assume radius of every sphere to be ' \(r\) '.
Question:
The empty space in this \(\mathrm{HCP}\) unit cell is

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Let \(V_r\) denotes the sum of the first \(r\) terms of an arithmetic progression \((A P)\) whose first term is \(r\) and the common difference is \((2 r-1)\). Let \(T_r=V_{r+1}-V_r-2\) and \(Q_r=T_{r+1}-T_r\) for \(r=1,2, \ldots\)
Question:
\(T_r\) is always

Dissolving \(120 \mathrm{~g}\) of urea (molecular weight 60) in \(1000 \mathrm{~g}\) of water gave a solution of density \(1.15 \mathrm{~g} / \mathrm{mL}\). The molarity of the solution is