The pH values of 0.1 M solution of HCl, CH₃COOH, NH₄Cl and CH₃COONa will have the order

• HCl <CH₃COOH < NH₄Cl <CH₃COONa 

• CH₃COONa <NH₄Cl<CH₃COOH <HCl

• NH₄Cl <CH₃COONa <CH₃COOH <HCl

• All will have same pH value

For the titration of solution of oxalic acid and sodium hydroxide, the suitable indicator is

• phenolphthalein

• methyl orange

• any of these

• None of these

C₂H₂ + $\frac{5}{2}{\mathrm{O}}_2$ → 2CO₂ + H₂O ; ΔH = -310 Kcal

C + O₂ → CO₂ ; ΔH = -94 Kcal

H₂ + $\frac{1}{2}{\mathrm{O}}_2$  →   H₂O ; ΔH = -68 Kcal

On the basis of the above equations, ΔH_f (enthalpy of formation) of C₂H₂ ,will be

• -148 Kcal

• +54 Kcal

• -54 Kcal

• +80 Kcal

I₂(s) $\rightleftharpoons$I₂(g) ΔH= + 40Kcal, ΔS= 80cal. The sublimation point of I₂(s) will be

• 100°C

• 127°C

• 227°C

• 500°C

In which of the following pairs both molecules do not possess same type of hybridisation?

• CH₄ and H₂O

• PCl₅ and SF₄

• SF₆ and XeF₄

• BCl₃ and NCl₃

If H-X bond length is 2.00 Å. and H-X bond has dipole moment 5.12 x 10^-30 C-m, the percentage of ionic character in the molecule will be

• 100%

• 16%

• 18%

• 20%

17.

(i) H—C—H angle in CH₄
(ii) Cl—B—Cl angle in BCl₃
(iii) F—I—F angle in IF₇ in a plane
(iv) I—I—I angle in I${}_3^{-}$

Increasing order of above bond angles is

• (i) < (ii)< (iii)< (iv)

• (ii)< (i) < (iii)< (iv)

• (iii)< (i)< (ii)< (iv)

• (iv)< (ii) < (i) < (iii)

• ${\mathrm{O}}_2^{2-}< {\mathrm{O}}_2^{-}<{\mathrm{O}}_2 <{\mathrm{O}}_2^{2+}$

• ${\mathrm{O}}_2^{2-}< {\mathrm{O}}_2<{\mathrm{O}}_2^{-}<{\mathrm{O}}_2^{2+}$

• ${\mathrm{O}}_2<{\mathrm{O}}_2^{2-}< {\mathrm{O}}_2^{-}<{\mathrm{O}}_2^{2+}$

• ${\mathrm{O}}_2 <{\mathrm{O}}_2^{2+}<{\mathrm{O}}_2^{2-}< {\mathrm{O}}_2^{-}$

The strongest ortho/para directing group is

• -NH₂

• -CH₃

• -Cl

• -C₂H₅

An organic alkadiene on reductive ozonolysis produces
(i) acetaldehyde
(ii) acetone
(iii) 2-methylpropane-1,3-dial
The formula of alkadiene will be

• CH₃C(CH₃)=CHCH(CH₃)CH=CHCH₃

• CH₃CH(CH₃)CH=C(CH₃)CH=CHCH₃

• CH₃C(CH₃)=CHCHC(CH₃)=CHCH₃

• CH₃CH₂CH(CH₃)CH=CHC(CH₃)=CH₂