'कार्बन डाइऑक्साइड' (CO₂) को 'शुष्क बर्फ' (Dry Ice) किस अवस्था में कहते हैं?

उत्तर: (A) ठोस / Solid — Solid CO₂ = Dry Ice (-78.5°C). It undergoes sublimation (solid → gas directly, skipping liquid). Used for: food preservation, fog effects in movies, shipping perishables. Called 'dry' because it doesn...