The 1st, 2nd and 3rd ionisation enthalpies, I₁, I₂ and I₃, of four atoms with atomic numbers n, n + 1, n + 2, and n + 3, where n < 10, are tabulated below. What is the value of n?

Consider the following compounds in the liquid form :

O₂, HF, H₂O, NH₃, H₂O₂, CCl₄, CHCl₃, C₆H₆, C₆H₅Cl

When a charged comb is brought near their flowing stream, how many of them show deflection as per the following figure?

In the chemical reaction between stoichiometric quantities of KMnO₄ and KI in weakly basic solution, what is the number of moles of I₂ released for 4 moles of KMnO₄ consumed?

An acidified solution of potassium chromate was layered with an equal volume of amyl alcohol. When it was shaken after the addition of 1 mL of 3% H₂O₂, a blue alcohol layer was obtained. The blue colour is due to the formation of a chromium (VI) compound 'X'. What is the number of oxygen atoms bonded to chromium through only single bond in a molecule of X?

The structure of a peptide is given below.


If the absolute values of the net charge of the peptide at $\mathrm{pH}$ $=2$, $\mathrm{pH}=6$, and $\mathrm{pH}=11$ are $\left|Z_1\right|,\left|Z_2\right|$, and $\left|Z_3\right|$, respectively, then what is $\left|Z_1\right|+\left|Z_2\right|+\left|Z_3\right|$?

An organic compound (C₈H₁₀O₂) rotates plane-porarised light. It produces pink color with neutral FeCl₃ solution. What is the total number of all the possible isomers for this compound?

In an experiment, m grams of a compound X (gas/liquid/solid) taken in a container is loaded in a balance as shown in figure I below.

In the presence of a magnetic field, the pan with X is either deflected upwards (figure II), or deflected downwards (figure III), depending on the compound X. Identify the correct statement(s).

Which of the following plots is(are) correct for the given reaction?

([P]₀ is the initial concentration of P)

Which among the following statement(s) is/are true for the extraction of aluminium from bauxite?

Choose the correct statement(s) among the following :

Consider the following four compounds, I, II, III, and IV.



Choose the correct statement(s)

Consider the following transformations of a compound P.



Choose the correct option(s).

A solution of 0.1 M weak base (B) is titrated with 0.1 M of a strong acid (HA). The variation of pH of the solution with the volume of HA added is shown in the figure below. What is the pK_b of the base? The neutralisation reaction is given by

$$B + HA\buildrel {} \over \longrightarrow B{H^ + } + {A^ - }$$

Liquids A and B form ideal solution for all compositions of A and B at 25$$^\circ $$C. Two such solutions with 0.25 and 0.50 mole fractions of A have the total vapour pressure of 0.3 and 0.4 bar, respectively. What is the vapour pressure of pure liquid B in bar?

The figure below is the plot of potential energy versus internuclear distance (d) of H₂ molecule in the electronic ground state. What is the value of the net potential energy E₀ (as indicated in the figure) in kJ mol^-1, for d = d₀ at which the electron-electron repulsion and the nucleus-nucleus repulsion energies are absent? As reference, the potential energy of H atom is taken as zero when its electron and the nucleus are infinitely far apart.
Use Avogadro constant as 6.023 $$ \times $$ 10²³ mol^-1.

Consider the reaction sequence from P to Q shown below. The overall yield of the major product Q from P is 75%. What is the amount in grams of Q obtained from 9.3 mL of P? (Use density of P = 1.00 g mL^-1; Molar mass of C = 12.0, H = 1.0, O = 16.0 and N = 14.0 g mol^-1)

Tin is obtained from cassiterite by reduction with coke. Use the data given below to determine the minimum temperature (in K) at which the reduction of cassiterite by coke would take place.

At $$298K:{\Delta _f}H^\circ [Sn{O_2}(s)] = - 581.0$$ mol^-1,

$$\eqalign{ & {\Delta _f}H^\circ [(C{O_2})(g)] = - 394.0\,kJ\,mol{ ^{-1}} \cr & S^\circ [Sn{O_2}(s)] = 56.0J\,{K^{ - 1}}mo{l^{ - 1}} \cr & S^\circ [Sn(s)] = 52.0\,J\,K{ ^{-1}}mo{l^{ - 1}} \cr & S^\circ [C(s)] = 6.0\,J\,{K^{ - 1}}mo{l^{ - 1}} \cr & S^\circ [C{O_2}(g)] = 210.0\,J\,{K^{ - 1}}mo{l^{ - 1}} \cr} $$

Assume that, the enthalpies and the entropies are temperature independent.

An acidified solution of 0.05 M Zn²⁺ is saturated with 0.1 M H₂S. What is the minimum molar concentration (M) of H⁺ required to prevent the precipitation of ZnS?

Use K_sp(ZnS) = 1.25 $$ \times $$ 10^$$-$$22 and overall dissociation constant of

H₂S, K_net = K₁K₂ = 1 $$ \times $$ 10^-21.