NTA JEE Main 25th February 2021 Shift 1

A car tyre is filled with nitrogen gas at 35 psi at 27°C. It will burst if pressure exceeds 40 psi. The temperature in °C at which the car tyre will burst is ______ (Rounded-off to the nearest integer)

The reaction of cyanamide, $$NH_2CN_{(s)}$$ with oxygen was run in a bomb calorimeter and $$\Delta U$$ was found to be $$-742.24$$ kJ mol$$^{-1}$$. The magnitude of $$\Delta H_{298}$$ for the reaction
$$NH_2CN_{(s)} + \frac{3}{2}O_{2(g)} \to N_{2(g)} + O_{2(g)} + H_2O_{(l)}$$ is ______ kJ. (Rounded off to the nearest integer) [Assume ideal gases and R = 8.314 J mol$$^{-1}$$ K$$^{-1}$$]

The ionization enthalpy of Na$$^+$$ formation from $$Na_{(g)}$$ is 495.8 kJ mol$$^{-1}$$, while the electron gain enthalpy of Br is $$-325.0$$ kJ mol$$^{-1}$$. Given the lattice enthalpy of NaBr is $$-728.4$$ kJ mol$$^{-1}$$. The energy for the formation of NaBr ionic solid is $$(-) \underline{\hspace{1cm}} \times 10^{-1}$$ kJ mol$$^{-1}$$

0.4 g mixture of NaOH, $$Na_2CO_3$$ and some inert impurities was first titrated with $$\frac{N}{10}$$ HCl using phenolphthalein as an indicator, 17.5 mL of HCl was required at the end point. After this methyl orange was added and titrated. 1.5 mL of same HCl was required for the next end point. The weight percentage of $$Na_2CO_3$$ in the mixture is ______ (Rounded-off to the nearest integer)

In basic medium $$CrO_4^{2-}$$ oxidises $$S_2O_3^{2-}$$ to form $$SO_4^{2-}$$ and itself changes into $$Cr(OH)_4^-$$. The volume of 0.154 M $$CrO_4^{2-}$$ required to react with 40 mL of 0.25 M $$S_2O_3^{2-}$$ is ______ mL. (Rounded-off to the nearest integer)

Using the provided information in the following paper chromatogram:

The calculated $$R_f$$ value of A is ______ $$\times 10^{-1}$$.

Consider the following chemical reaction.
$$CH \equiv CH \xrightarrow[2) CO, HCl, AlCl_3]{1) \text{Red hot Fe tube, 873 K}}$$ Product
The number of $$sp^2$$ hybridized carbon atom(s) present in the product is ______

1 molal aqueous solution of an electrolyte $$A_2B_3$$ is 60% ionised. The boiling point of the solution at 1 atm is ______ K. (Rounded-off to the nearest integer) [Given $$K_b$$ for $$H_2O = 0.52$$ K kg mol$$^{-1}$$]

For the reaction, $$aA + bB \to cC + dD$$, the plot of log k v/s $$\frac{1}{T}$$ is given below:

The temperature at which the rate constant of the reaction is $$10^{-4}$$ s$$^{-1}$$ is ______ K.
(Rounded-off to the nearest integer) [Given: The rate constant of the reaction is $$10^{-5}$$ s$$^{-1}$$ at 500 K.]

Among the following, the number of halide(s) which is/are inert to hydrolysis is ______
(A) $$BF_3$$
(B) $$SiCl_4$$
(C) $$PCl_5$$
(D) $$SF_6$$