Same chapter3 marksDifficulty: Medium
Draw the electron dot structure of a molecule of methane and of ammonia, and state the number of lone pairs in each.
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3 marksDifficulty: Medium
State three differences between electrovalent and covalent compounds.
Original Khojo Papers practice question — not from a past board paper.
Answer
Electrovalent compounds are usually crystalline solids with high melting and boiling points, they dissolve in water and conduct electricity in the molten or aqueous state. Covalent compounds are usually gases, liquids or soft solids with low melting and boiling points, they are generally insoluble in water but soluble in organic solvents, and they do not conduct electricity.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The difference follows from the strong electrostatic forces between ions against the weak forces between covalent molecules.
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