Which of the following salts forms an acidic aqueous solution? MCQ with Answer and Explanation

Explanation:
In graphite, each carbon is sp² hybridized and bonded to three others, leaving one p-orbital electron delocalized across the layer. These free electrons allow conduction parallel to layers.

Explanation:
Silicon is a metalloid, possessing properties intermediate between metals and non-metals. It has a metallic luster but is brittle and a semiconductor. Other metalloids include boron, germanium, arsenic, antimony, tellurium. Sodium and calcium are metals (good conductors, malleable). Chlorine is a non-metal (gas, poor conductor). Metalloids are found along the zigzag line in the p-block of the periodic table.

Explanation:
In Fe₂O₃, oxygen has valency 2. Two Fe atoms combined with three O atoms: total negative charge = 6. For two Fe, total positive = 6, so each Fe has +3. Valency = 3 (ferric). In FeO, valency is 2 (ferrous).