11.

Which pair of elements has same chemical properties?

• 13, 22

• 3, 11

• 4, 24

• 2, 4

Heat formation of H₂O is -188 kJ/ mol and H₂O₂ is 286 kJ/mol. The enthalpy change for the reaction; 2H₂O₂ → 2H₂O + O₂ is

• 196 kJ

• -196 kJ

• 984 kJ

• -984 kJ

When 1 mole of a gas is heated at constant volume, temperature is raised from 298 K to 308 K. Heat supplied to the gas is 500J. Then, which statement is correct?

• q= -W = 500J : ΔE= 0

• q= W = 500J : ΔE= 0

• q = ΔE= 500J , W= 0

• ΔE = 0; q= W = -500J

The reaction, 10FeSO₄ + 2KMnO₄ + 8H₂SO₄ → 2MnSO₄ + 5Fe(SO₄)₃ + K₂SO₄ + 8H₂O is an example of reaction of 

• disproportionation

• intermolecular redox

• intramolecular redox

• None of these

The compound that can work both as an oxidising as well as reducing agent is

• KMnO₂

• H₂O₂

• Fe₂(SO₄)₃

• K₂Cr₂O₇

Standard electrode potential data are useful for understanding the suitability of an oxidant in a redox titration. Some half cell reactions and their standard potentials are given below

$$\begin{gathered} {\mathrm{MnO}}_4^{-}\left(\mathrm{aq}\right) + 8{\mathrm{H}}^{+}\left(\mathrm{aq}\right) + 5{\mathrm{e}}^{-} \to {\mathrm{Mn}}^{2+}\left(\mathrm{aq}\right) + 4{\mathrm{H}}_2\mathrm{O} \left(\mathrm{l}\right): {\mathrm{E}}^{°}= 1.51\mathrm{V} \\ {\mathrm{Cr}}_2{\mathrm{O}}_7^{2-}\left(\mathrm{aq}\right) + 14{\mathrm{H}}^{+}+ 6{\mathrm{e}}^{\mathrm{\_}} \to 2{\mathrm{Cr}}^{3+} + 7{\mathrm{H}}_2\mathrm{O} \left(\mathrm{l}\right): {\mathrm{E}}^{°}= 1.38\mathrm{V} \\ {\mathrm{Fe}}^{3+}\left(\mathrm{aq}\right) + {\mathrm{e}}^{-} \to {\mathrm{Fe}}^{2+}\left(\mathrm{aq}\right); {\mathrm{E}}^{°}=0.77\mathrm{V} \\ {\mathrm{Cl}}_2\left(\mathrm{g}\right) + 2{\mathrm{e}}^{-} \to 2{\mathrm{Cl}}^{-}\left(\mathrm{aq}\right); {\mathrm{E}}^{°}=1.40\mathrm{V} \end{gathered}$$

Identify the incorrect statement regarding the quantitative estimation of gaseous Fe(NO₃)₂.

• MnO${}_4^{-}$ can be used in aqueous HCl

• Cr₂O${}_7^{2-}$ can be used in aqueous HCl

• MnO${}_4^{-}$ can be used in aqueous H₂SO₄

• Cr₂O${}_7^{2-}$ can be used in aqueous H₂SO₄

In Zeigler Natta polymerisation of ethylene, the active species is

• AlCl₃

• Et₃Al

• CH₂CH₂

• Ti³⁺

The number of possible alkynes with molecular formula C₅H₈ is

• 1

• 3

• 5

• 8

Which of the following orders is not correct regarding the -I effect of the substituents?

• —SR < —OR <—O⁺R₂

• —N⁺R₂ < —OR<—F
  

• —I< —Cl <—Br < —F

• —N⁺R₃<—O⁺R₂ <—OR

Which of the following types of reaction occurs when a substituent has got a double bond with evenly distributed π-electron cloud?

• Electrophilic addition

• Nucleophilic addition

• Electrophilic substitution

• Nucleophilic substitution