\[\underset{\begin{smallmatrix} 2\,mol \\ \left( 2\times 206\,=\,412\,g \right) \end{smallmatrix}}{\mathop{2{{C}_{8}}{{H}_{7}}SO_{3}^{-}N{{a}^{+}}}}\,+\underset{1\,mol}{\mathop{C{{a}^{2+}}}}\,\to \]     \[{{\left( {{C}_{8}}{{H}_{7}}SO_{3}^{-} \right)}_{2}}C{{a}^{2+}}+2N{{a}^{+}}\]
$$1\,mol\,\,{\text{of}}\,\,C{a^{2 + }} = 412\,g\,\,{\text{of}}\,\,{\text{resin}}$$
Maximum uptake of $$C{a^{2 + }}$$  ions by the resin $$ = \frac{{1\,mol}}{{412\,g}} = \frac{1}{{412}}mol/g$$

No explanation is given for this question. Let's discuss the answer together.

$$\eqalign{ & {H_2}{O_2} \equiv KI \equiv {I_2} \cr & mEq\,\,{\text{of}}\,{H_2}{O_2} = 5 \times N \cr & mEq\,\,{\text{of}}\,{I_2} = \frac{{{\text{Weight}}}}{{E.w}} \times 1000 \cr & \frac{{1.27}}{{127}} \times 1000 = 10\,mEq \cr & {I_2} = M.w = 254 \cr & E.w = \frac{{M.w}}{2} = \frac{{254}}{2} = 127 \cr & \therefore \,\,mEq\,{\text{of}}\,{H_2}{O_2} = mEq\,{\text{of}}\,{I_2} \cr & 5 \times N = 10\,\,\,\,\therefore \,\,N = 2 \cr & 1\,N\,{\text{of}}\,{H_2}{O_2} = 1.7\% \,{\text{of}}\,{H_2}{O_2} \cr & 2\,N\,{\text{of}}\,{H_2}{O_2} = 3.4\% \,{\text{of}}\,{H_2}{O_2} \cr} $$

Pure para form can be obtained at low temperature $$(20K)$$  but pure ortho form is very difficult to obtain.

The reaction in which two molecules of the same species react to give ions by proton transfer is known as auto - protolysis or self ionisation. In this reaction. proton from one $${H_2}O$$  molecule is transferred to another $${H_2}O$$  molecule.
$$\mathop {{H_2}{O_{\left( l \right)}}}\limits_{{\text{Acid}}} + \mathop {{H_2}{O_{\left( l \right)}}}\limits_{{\text{Base}}} \rightleftharpoons \mathop {{H_3}O_{\left( {aq} \right)}^ + }\limits_{{\text{Conjugate acid}}} + \mathop {OH_{\left( {aq} \right)}^ - }\limits_{{\text{Conjugate base}}} $$

\[\underbrace{CO+{{H}_{2}}}_{\text{water gas}}+{{H}_{2}}O\xrightarrow{\text{catalyst}}C{{O}_{2}}+2{{H}_{2}}\]

$${H_2}{O_2}$$  shows non-planar structure. It has a half opened book like structure in which the two $$O - H$$  groups lie on the two pages of the book.

$$O-O$$  single bond distance is $$1.48\mathop {\text{A}}\limits^{\text{o}} $$

$${H_2}O$$  absorbs neutrons more than $${D_2}O$$  and this decreases the number of neutrons for the fission process.

Syngas also known as synthetic gas, is the name given to all the mixtures of $$CO$$  and $${H_2}$$  irrespective of their composition.

Ortho and para forms of hydrogen resemble in their chemical properties.