The ground state energy of hydrogen atom is $$-$$13.6 eV. Consider an electronic state $$\psi $$ of He⁺ whose energy, azimuthal quantum number and magnetic quantum number are $$-$$3.4 eV, 2 and 0, respectively.

Which of the following statement(s) is(are) true for the state $$\psi $$?

Consider the following reactions (unbalanced).

$$Zn + Hot\,conc.\,{H_2}S{O_4}\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{}} G + R + X$$

$$Zn + conc.\,NaOH\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{}} T + Q$$

$$G + {H_2}S + N{H_4}OH\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{}} Z\,(a\,precipitate) + X + Y$$

Choose the correct option(s).

With reference to aqua-regia, choose the correct option(s).

Choose the correct option(s) from the following.