An atom of element X has 6 protons and 8 neutrons. Its mass number is: MCQ with Answer and Explanation

Explanation:
Reactivity series orders metals according to their ease of oxidation—i.e., losing electrons to form cations. At the top (K, Na) are strong reducing agents, reacting vigorously with water and acids; at the bottom (Au, Pt) are noble metals, resistant to corrosion. The series helps predict displacement reactions and extraction methods. Mnemonic: 'Please Stop Calling Me A Cute Zebra...' etc.

Explanation:
Filtration uses filter paper or other porous medium that allows liquid to pass but retains solid particles. Distillation separates liquids by boiling points; sublimation separates sublimable solids; chromatography separates based on differential adsorption. Example: separating sand from water.

Explanation:
Sodium reacts vigorously with moisture and oxygen in air, so it is stored under kerosene to prevent contact. Potassium, lithium are similarly stored. Iron, zinc, copper do not require such storage.