NTA JEE Main 1st February 2023 Shift 2

All structures given below are of vitamin C. Most stable of them is:

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): $$\alpha$$-halocarboxylic acid on reaction with dil. NH$$_3$$ gives good yield of $$\alpha$$-amino carboxylic acid whereas the yield of amines is very low when prepared from alkyl halides.
Reason (R): Amino acids exist in zwitter ion form in aqueous medium.
In the light of the above statements, choose the correct answer from the options given below:

The molality of a $$10\%(v/V)$$ solution of di-bromine solution in CCl$$_4$$ (carbon tetrachloride) is x. $$x = $$ ______ $$\times 10^{-2}$$ M. (Nearest integer)
[Given: molar mass of Br$$_2 = 160$$ g mol$$^{-1}$$, atomic mass of C $$= 12$$ g mol$$^{-1}$$, atomic mass of Cl $$= 35.5$$ g mol$$^{-1}$$, density of dibromine $$= 3.2$$ g cm$$^{-3}$$, density of CCl$$_4 = 1.6$$ g cm$$^{-3}$$]

$$0.3$$ g of ethane undergoes combustion at $$27°$$C in a bomb calorimeter. The temperature of calorimeter system (including the water) is found to rise by $$0.5°$$C. The heat evolved during combustion of ethane at constant pressure is ______ kJ mol$$^{-1}$$. (Nearest integer)
[Given: The heat capacity of the calorimeter system is $$20$$ kJ K$$^{-1}$$, R $$= 8.3$$ JK$$^{-1}$$ mol$$^{-1}$$. Assume ideal gas behaviour. Atomic mass of C and H are 12 and 1 g mol$$^{-1}$$ respectively]

$$20\%$$ of acetic acid is dissociated when its 5 g is added to 500 mL of water. The depression in freezing point of such water is ______ $$\times 10^{-3}$$ °C. Atomic mass of C, H and O are 12, 1 and 16 a.m.u. respectively.
[Given: Molal depression constant and density of water are $$1.86$$ K kg mol$$^{-1}$$ and $$1$$ g cm$$^{-3}$$ respectively]

$$1 \times 10^{-5}$$ M AgNO$$_3$$ is added to $$1$$ L of saturated solution of AgBr. The conductivity of this solution at 298 K is _______ $$\times 10^{-8}$$ S m$$^{-1}$$.
[Given: K$$_{sp}$$(AgBr) $$= 4.9 \times 10^{-13}$$ at 298 K, $$\lambda^{0}_{\text{Ag}^+} = 6 \times 10^{-3}$$ Sm$$^2$$ mol$$^{-1}$$, $$\lambda^{0}_{\text{Br}^-} = 8 \times 10^{-3}$$ Sm$$^2$$ mol$$^{-1}$$, $$\lambda^{0}_{\text{NO}_3^-} = 7 \times 10^{-3}$$ Sm$$^2$$ mol$$^{-1}$$]

$$\text{A} \to \text{B}$$
The above reaction is of zero order. Half life of this reaction is $$50$$ min. The time taken for the concentration of A to reduce to one-fourth of its initial value is ______ min. (Nearest integer)

Among following compounds, the number of those present in copper matte is ______
A. CuCO$$_3$$
B. Cu$$_2$$S
C. Cu$$_2$$O
D. FeO

The spin only magnetic moment of $$[\text{Mn}(\text{H}_2\text{O})_6]^{2+}$$ complexes is ______ B.M. (Nearest integer). (Given atomic number of Mn $$= 25$$)

Among the following, the number of tranquilizer/s is/are ______
A. Chlorodiazepoxide
B. Veronal
C. Valium
D. Salvarsan