The number of protons in ¹⁸O is: MCQ with Answer and Explanation

Explanation:
Across a period, nuclear charge increases while electrons are added to the same shell, leading to stronger attraction, so atomic radius decreases and ionization energy generally increases (with some exceptions like N to O due to half-filled stability). Metallic character decreases, non-metallic character increases. Electron affinity becomes more negative (increases in magnitude). Exam note: Ionization energy trend: Increases across period, decreases down group.

Explanation:
Aluminium oxide: Al³⁺ and O²⁻. To balance charges, 2 Al³⁺ (total +6) combine with 3 O²⁻ (total -6). Thus valency of Al is 3. It loses three electrons. Formula determined by criss-cross method.

Explanation:
Faraday's First Law of Electrolysis states that the mass of a substance deposited or liberated at an electrode is directly proportional to the total charge (Q) passed through the electrolyte (m = ZQ, where Z is the electrochemical equivalent). The Second Law relates mass to equivalent weight.