Measurement of Matter

Na⁺, Ca²⁺, NH₄⁺

Basic radicals are positively charged ions (cations). Na⁺, Ca²⁺, and NH₄⁺ are all positively charged, while Cl⁻, SO₄²⁻, and OH⁻ are negatively charged acidic radicals.

Antoine Lavoisier

Antoine Lavoisier is known as the father of modern chemistry. He discovered the law of conservation of mass and made significant contributions to chemical nomenclature.

H₂O, NaCl, CO₂

Compounds are formed by chemical combination of different elements. H₂O, NaCl, and CO₂ contain different elements, while O₂ and N₂ are molecules of the same element.

44 g

Molecular mass of CO₂ = 12 + (2 × 16) = 12 + 32 = 44 u. One mole of any substance has mass in grams equal to its molecular mass in u.