Q.Justify the position of hydrogen in the periodic table?

Step 1. Hydrogen's electronic configuration is $1s^1$, matching the general alkali-metal valence pattern $ns^1$.

Step 2. Like the alkali metals, hydrogen forms a unipositive ion H⁺, forms analogous compounds (halides, oxides, peroxides, sulphides paralleling the alkali metals' own), and acts as a reducing agent -- though its ionisation energy (1,314 kJ mol⁻¹) is far higher than any alkali metal's.

Step 3. Hydrogen also shows a partial halogen-like character, being able to gain one electron to form H⁻ (paralleling X⁻) -- but its electron affinity is much smaller than a halogen's, so this tendency is comparatively weak (forming H⁻ even costs energy, unlike the energy released forming X⁻). …

Lay out hydrogen's alkali-metal-like traits, its weaker halogen-like traits, and conclude with which pattern (+1 oxidation state) ac …

• Giving only the alkali-metal similarities without acknowledging (and then setting aside) the halogen-like H- tendency -- a full 'justification' …