Writing formulae by criss-crossक्रॉस-गुणन (क्रिस-क्रॉस) विधि से सूत्र लिखना

NCERT Sec 9.5 · interactive diagram

Parts and their functions

• Aluminium oxide, Al₂O₃ (ऐलुमिनियम ऑक्साइड, Al₂O₃) — Al³⁺ and O²⁻: cross the numbers 3 and 2 → Al₂O₃. Check: 2 × (+3) + 3 × (−2) = 0.
• Magnesium oxide, MgO (मैग्नीशियम ऑक्साइड, MgO) — Crossing gives Mg₂O₂; divide by the common factor 2 → MgO (simplest ratio).
• Calcium chloride, CaCl₂ (कैल्सियम क्लोराइड, CaCl₂) — Ca²⁺ and Cl⁻ → CaCl₂ (subscript 1 is not written). Charges are not shown in the final formula.

Original diagram drawn by Simple Learning Hub, based on NCERT Sec 9.5. Report a mistake