The alcohol that is poisonous and can cause blindness is: MCQ with Answer and Explanation

Explanation:
CH₄ (methane) has covalent bonds where carbon shares electrons with four hydrogen atoms. CaO (Ca²⁺ O²⁻), KCl, and NaF are ionic compounds formed by electron transfer between a metal and a non-metal. Ionic bonds form when electronegativity difference is large. Covalent bonds typically between non-metals with similar electronegativities.

Explanation:
Petroleum originates from microscopic marine organisms (plankton) that sank to the seabed and were transformed by heat/pressure over millions of years. Coal is from land plants.

Explanation:
Sodium carbonate (Na₂CO₃), also called soda ash, is a key ingredient in glass manufacturing. It lowers the melting point of silica (SiO₂) and provides sodium oxide. The glass batch consists of sand (SiO₂), soda ash (Na₂CO₃), and limestone (CaCO₃). Sodium chloride is table salt, potassium nitrate used in gunpowder, ammonium chloride in batteries/leclanche cells.