Which of the following species is isoelectronic with CO? MCQ with Answer and Explanation

Explanation:
Fertilizer grade is expressed as N-P₂O₅-K₂O percentage by mass. So 15-15-15 means 15% N, 15% P₂O₅ (not elemental P), and 15% K₂O (not elemental K). To convert P₂O₅ to P, multiply by 0.44; K₂O to K by 0.83. This is a balanced compound fertilizer providing all three primary macronutrients.

Explanation:
Camphor sublimes—it directly changes from solid to vapor on heating without passing through the liquid phase. Other sublimable solids include naphthalene, iodine, ammonium chloride, and dry ice (solid CO₂). Sodium chloride, sugar, and sand melt or decompose on strong heating. Sublimation is used to separate sublimable substances from non-sublimable impurities. The process requires careful heating.

Explanation:
Eka-aluminium was later discovered and named gallium. Eka-silicon is germanium; eka-boron is scandium. Mendeleev's predictions were remarkably accurate.