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Given below are two statements:
Statement - I: Along the period, the chemical reactivity of the element gradually increases from group 1 to group 18.
Statement - II: The nature of oxides formed by group 1 element is basic while that of group 17 elements is acidic.
In the light of the above statements, choose the most appropriate from the options given below:
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Given below are two statements:
Statement-I: Since fluorine is more electronegative than nitrogen, the net dipole moment of $$NF_3$$ is greater than $$NH_3$$.
Statement-II: In $$NH_3$$, the orbital dipole due to lone pair and the dipole moment of NH bonds are in opposite direction, but in $$NF_3$$ the orbital dipole due to lone pair and dipole moments of N-F bonds are in same direction.
In the light of the above statements, choose the most appropriate from the options given below.
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Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: $$H_2Te$$ is more acidic than $$H_2S$$.
Reason R: Bond dissociation enthalpy of $$H_2Te$$ is lower than $$H_2S$$.
In the light of the above statements, choose the most appropriate from the options given below.
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IUPAC name of the following compound is:
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Which among the following purification methods is based on the principle of "Solubility" in two different solvents?
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The correct stability order of carbocations is
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Product A and B formed in the following set of reactions are:
If a substance '$$A$$' dissolves in solution of a mixture of '$$B$$' and '$$C$$' with their respective number of moles as $$n_A$$, $$n_B$$ and $$n_C$$, mole fraction of $$C$$ in the solution is:
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The solution from the following with highest depression in freezing point/lowest freezing point is
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Reduction potential of ions are given below:
$$ClO_4^-$$: $$E° = 1.19$$ V; $$IO_4^-$$: $$E° = 1.65$$ V; $$BrO_4^-$$: $$E° = 1.74$$ V
The correct order of their oxidising power is:
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Choose the correct statements about the hydrides of group 15 elements.
A. The stability of the hydrides decreases in the order $$NH_3 > PH_3 > AsH_3 > SbH_3 > BiH_3$$
B. The reducing ability of the hydrides increases in the order $$NH_3 < PH_3 < AsH_3 < SbH_3 < BiH_3$$
C. Among the hydrides, $$NH_3$$ is strong reducing agent while $$BiH_3$$ is mild reducing agent.
D. The basicity of the hydrides increases in the order $$NH_3 < PH_3 < AsH_3 < SbH_3 < BiH_3$$
Choose the most appropriate from the options given below:
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The orange colour of $$K_2Cr_2O_7$$ and purple colour of $$KMnO_4$$ is due to
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$$A$$ and $$B$$ formed in the following reactions are:
$$CrO_2Cl_2 + 4NaOH \rightarrow A + 2NaCl + 2H_2O$$
$$A + 2HCl + 2H_2O_2 \rightarrow B + 3H_2O$$
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Alkaline oxidative fusion of $$MnO_2$$ gives "A" which on electrolytic oxidation in alkaline solution produces $$B$$. $$A$$ and $$B$$ respectively are:
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The molecule/ion with square pyramidal shape is:
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The coordination geometry around the manganese in decacarbonyldimanganese(0) is:
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Given below are two statements:
Statement - I: High concentration of strong nucleophilic reagent with secondary alkyl halides which do not have bulky substituents will follow $$S_N2$$ mechanism.
Statement - II: A secondary alkyl halide when treated with a large excess of ethanol follows $$S_N1$$ mechanism.
In the light of the above statements, choose the most appropriate from the options given below:
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Salicylaldehyde is synthesized from phenol, when reacted with
m-chlorobenzaldehyde on treatment with 50% KOH solution yields
The products A and B formed in the following reaction scheme are respectively:
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Number of spectral lines obtained in $$He^+$$ spectra, when an electron makes transition from fifth excited state to first excited state will be
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Two reactions are given below:
$$2Fe_{(s)} + \frac{3}{2}O_{2(g)} \rightarrow Fe_2O_{3(s)}$$, $$\Delta H° = -822$$ kJ/mol
$$C_{(s)} + \frac{1}{2}O_{2(g)} \rightarrow CO_{(g)}$$, $$\Delta H° = -110$$ kJ/mol
Then enthalpy change for following reaction:
$$3C_{(s)} + Fe_2O_{3(s)} \rightarrow 2Fe_{(s)} + 3CO_{(g)}$$
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The pH of an aqueous solution containing 1M benzoic acid ($$pK_a = 4.20$$) and 1M sodium benzoate is 4.5. The volume of benzoic acid solution in 300 mL of this buffer solution is _________ mL.
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Total number of species from the following which can undergo disproportionation reaction: $$H_2O_2$$, $$ClO_3^-$$, $$P_4$$, $$Cl_2$$, $$Ag$$, $$Cu^{+1}$$, $$F_2$$, $$NO_2$$, $$K^+$$
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Number of geometrical isomers possible for the given structure is/are ________.
$$NO_2$$ required for a reaction is produced by decomposition of $$N_2O_5$$ in $$CCl_4$$ as by equation:
$$2N_2O_{5(g)} \rightarrow 4NO_{2(g)} + O_{2(g)}$$
The initial concentration of $$N_2O_5$$ is 3 mol L$$^{-1}$$ and it is 2.75 mol L$$^{-1}$$ after 30 minutes. The rate of formation of $$NO_2$$ is $$x \times 10^{-3}$$ mol L$$^{-1}$$ min$$^{-1}$$, value of $$x$$ is ________.
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Number of complexes which show optical isomerism among the following is _________.
$$cis-[Cr(ox)_2Cl_2]^{3-}$$, $$[Co(en)_3]^{3+}$$, $$cis-[Pt(en)_2Cl_2]^{2+}$$, $$cis-[Co(en)_2Cl_2]^+$$, $$trans-[Pt(en)_2Cl_2]^{2+}$$, $$trans-[Cr(ox)_2Cl_2]^{3-}$$
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2-chlorobutane + $$Cl_2 \rightarrow C_4H_8Cl_2$$ (isomers)
Total number of optically active isomers shown by $$C_4H_8Cl_2$$, obtained in the above reaction is ________.
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Number of metal ions characterized by flame test among the following is _________.
$$Sr^{2+}$$, $$Ba^{2+}$$, $$Ca^{2+}$$, $$Cu^{2+}$$, $$Zn^{2+}$$, $$Co^{2+}$$, $$Fe^{2+}$$
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The total number of correct statements, regarding the nucleic acids is _________.
A. RNA is regarded as the reserve of genetic information.
B. DNA molecule self-duplicates during cell division.
C. DNA synthesizes proteins in the cell.
D. The message for the synthesis of particular proteins is present in DNA.
E. Identical DNA strands are transferred to daughter cells.
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