Some Basic Concepts of Chemistry — Important Questions

Have lustre, Good conductors of heat and electricity, Malleable and ductile

Metals typically have lustre (shiny appearance), conduct heat and electricity well, and can be hammered into sheets (malleable) or drawn into wires (ductile). They are not brittle.

Equal volumes of gases at same T and P contain equal molecules, It helps explain Gay-Lussac's law

Avogadro's law states equal volumes of gases at same temperature and pressure contain equal number of molecules. It applies to all gases and helps explain volume relationships in reactions.

6.022 × 10²³ mol⁻¹

Avogadro's constant (Nₐ) is 6.022 × 10²³ mol⁻¹, representing the number of particles in one mole of any substance.

Carbon-12

Carbon-12 is the standard for atomic mass. One atomic mass unit (u) is defined as 1/12 of the mass of one carbon-12 atom.