The Lassaigne’s extract is boiled with conc. ${\mathrm{HNO}}_3$ while testing for halogens, because it:

1. Helps in the precipitation of $\mathrm{AgCl}$
2. Increases the solubility product of $\mathrm{AgCl}$
3. Increases the concentration of ${\mathrm{NO}}_3^{-}$ ions
4. Decomposes ${\mathrm{Na}}_2\mathrm{S}$ and $\mathrm{NaCN}$, if formed

The most stable conformation of n-butane among the following is:

1.		2.
3.		4.

The correct order of acidity among the following is:

The correct order regarding the electronegativity of hybrid orbitals of carbon is:

1. $sp>s{p}^2<s{p}^3$

2. $sp>s{p}^2>s{p}^3$

3. $sp<s{p}^2>s{p}^3$

4. $sp<s{p}^2<s{p}^3$

Among the following groups maximum –I effect is exerted by:

\(1 . - C_{6} H_{5}\)
\(2 .\) \(- \left(OCH\right)_{3}\)
\(3 .\) \(- Cl\)
\(4 .\) \(-NO_2\)

The correct order of increasing bond length of  C-H, C-O, C-C and C=C is:

1.  $\mathrm{C}-\mathrm{C}<\mathrm{C}=\mathrm{C}<\mathrm{C}-\mathrm{O}<\mathrm{C}-\mathrm{H}$

2.  $\mathrm{C}-\mathrm{O}<\mathrm{C}-\mathrm{H}<\mathrm{C}-\mathrm{C}<\mathrm{C}=\mathrm{C}$

3.  $\mathrm{C}-\mathrm{H}<\mathrm{C}-\mathrm{O}<\mathrm{C}-\mathrm{C}<\mathrm{C}=\mathrm{C}$

4.  $\mathrm{C}-\mathrm{H}<\mathrm{C}=\mathrm{C}<\mathrm{C}-\mathrm{O}<\mathrm{C}-\mathrm{C}$

The structure of the compound whose IUPAC name is 3-Ethyl-2-hydroxy-4-methylhex-3-en-5-ynoic acid is:

1.		2.
3.		4.

In Kjeldahl’s method for estimation of nitrogen present in the soil sample, ammonia evolved from 0.75g of sample neutralized 10ml. of 1M H₂SO₄. The percentage of nitrogen in the soil is:

The correct order with respect to –I effect of the substituents is:
(R = alkyl)

1. -NH₂ > - OR < - F
2. -NR₂ < -OR < - F
3. -NH₂ > - OR > - F
4. -NR₂ > - OR > - F