The wavelength of photon 'A' is 400 nm. The frequency of photon 'B' is $10^{16} \ \text{s}^{-1}$. The wave number of photon 'C' is $10^4 \ \text{cm}^{-1}$. The correct order of energy of these photons is :

The reactions which produce alcohol as the product are :

A. $\mathrm{CH}_4 + \mathrm{O}_2 \xrightarrow{\mathrm{Mo}_2\mathrm{O}_3,\ \Delta} $

B. $2\mathrm{CH}_3\mathrm{CH}_3 + 3\mathrm{O}_2 \xrightarrow{(\mathrm{CH}_3\mathrm{COO})_2\mathrm{Mn},\ \Delta} $

C. $(\mathrm{CH}_3)_3\mathrm{CH} \xrightarrow{\mathrm{KMnO}_4} $

D. $ 2\mathrm{CH}_4 + \mathrm{O}_2 \xrightarrow{\mathrm{Cu}/523\ \mathrm{K}/100 \ \mathrm{atm}.} $

E. $\mathrm{CH}_3-\mathrm{CH}=\mathrm{CH}-\mathrm{CH}_3 \xrightarrow{\mathrm{KMnO}_4/\mathrm{H}^+} $

Choose the correct answer from the options given below :

For the given reaction;

CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂

If 90 g CaCO₃ is added to 300 mL of HCl which contains 38.55% HCl by mass and has density 1.13 g mL⁻¹, then which of the following option is correct?

Given molar mass of H, Cl, Ca and O are 1, 35.5, 40 and 16 g mol⁻¹ respectively.

Consider the elements N, P, O, S, Cl and F. The number of valence electrons present in the elements with most and least metallic character from the above list is respectively.