White phosphorous shows chemiluminescence because it:

Choose the correct statements from the following :
(A) two different solutions of sucrose of same molality prepared in different solventswill have the same depression in freezing point.
(B) the osmotic pressure of a solution is given by the equation \(II = CRT\) (where C is the molarity of the solution)
(C) decreasing order of osmotic pressure for 0.01 M aqueous solution of \(BaCl _2, KCl , CH _3 COOH\), and sucrose is \(BaCl _2 > KCl > CH _3 COOH >\) sucrose
(D) according to Raoult's law the vapor pressure exerted by a volatile component of asolution is directly proportional to its mole fraction in the solution
Choose the correct answer from the options given below :

A graph is plotted between \(\text{ln}\ k\) and \(\frac{1}{T}\). What is the value of slope?

What is the symbol of technetium element ?

Identify the product ' \(X\) ' and ' \(Y\) ' in the following reaction.

Answer the question on the basis of passage given below:
In the periodic table, the d-block contains the elements of group \(3\) to \(12\). The d-orbitals are progressively filled in each of the four long periods. The elements of d block referred as transition metals have partly filled d orbitals and exhibit certain characteristic properties such as variety of oxidation states, formation of coloured ions, act as catalyst and show paramagnetic behaviour.
The two inner transition metals series \(4f\) and \(5f\) are known as Lanthanoids and Actinoids respectively. The lanthanoids resemble one another more closely as compared to ordinary transition elements in any series.
In context of the Lanthanoids, which of the following statements is/are NOT correct?
A. There is a gradual decrease in the radii of the members with increasing atomic number in the series
B. Availability of \(4f\) electrons results in the formation of compounds in \(+4\) oxidation state for all the members of the series
C. Because of similar properties, the separation of lanthanoids is not easy
D. \(La(OH)_3\) is least basic among hydroxides of lanthanoids
E. Ce can act as an oxidising agent
Choose the correct answer from the options given below:

Answer the question on basis of passage given below :
Look at the following chemical reactions and answer the following question:
(A) \(C_7H_8 \xrightarrow{\text{Conc. HNO}_3, 0^\circ C}
(B) \xrightarrow{Sn/HCl}
(C) \xrightarrow{NaNO_2/H_3O^+}
(D) \xrightarrow{H_2O, Heat} (E)\)
(E) \(CH_3I \xrightarrow{KMnO_4/H^+}
(F) \xrightarrow{H_3O^+}
(G) \xrightarrow{NaOH} (H)\)
Which of the following compounds will form dimer ?

Which of the following is the best reducing agent to convert RCOOH into \(RCH _2 OH\) ?

Which of the following is a man-made ecosystem?

Assume that an electric field \( (20\hat{i}) \text{ V m}^{-1} \) exists in the region of space. If \( V_0 \) is the potential at the origin and \( V_A \) is the potential at \( x = 1 \text{ m} \), then the potential difference \( V_A - V_0 \) is :

Transition metals form a large number of complexes or coordination compounds in which the metal atoms are bound to a number of anions or neutral molecules. The valence bond theory explain the formation, magnetic behaviour and geometrical shapes while the crystal field theory explains the effect of different crystal fields on the degeneracy of d-orbitals energies of the central metal atom/ion. This provides for the quantitative estimation of orbital separation energies, magnetic moments and spectral and stability parameters.
Two complexes of nickel have same geometry but different magnetic behaviour are:
(A) \(\text{[Ni(CN)}_4]^{2-}\)
(B) \(\text{[Ni(CO)}_4]\)
(C) \(\text{[NiCl}_4]^{2-}\)
(D) \(\text{[Ni(NH}_3)_6]^{2+}\)
Choose the correct answer from the options given below :

Read the following passage carefully and answer the given questions.
Theory of Evolution
The evolution of life is a gradual process through which simple organisms are transformed into complex life forms over billions of years. It involves genetic changes, adaptation to the environment, and the emergence of diversity in species. Fossil records provide evidence of extinct life forms and transitional stages. Evolution is influenced by factors such as mutation, genetic recombination, and environmental pressure, shaping the biodiversity we see today. Charles Darwin and Alfred Russel Wallace were pioneering naturalists who developed the theory of evolution by natural selection.
According to Darwin, the term 'Fitness' in the context of natural selection refers to:

If \(A\) and \(B\) are square matrices of the same order, then \((A+B)(A-B)\) is equal to