C1a

Atomic Structure

Atoms consist of:

• protons - positive - in nucleus
• electrons -  negative
• neutrons - neutral - in nucleus

Compounds -  formed when 2 or more different kinds of atoms join together

Periodic table

• more than 100 elements
• vertical collumns = groups - contain similar properties
• e.g group 1 contains v.reactive metals - Sodium (Na)

Limestone - mainly calcium carbonate (CaCO3)

Thermal Decomposition - Quicklime

calcium carbonate calcium oxide (quicklime) + carbon dioxide

CaCO₃ CaO (quicklime) + CO₂

_{Slaked Lime}

calcium oxide + water → calcium hydroxide (slaked lime)

CaO + H₂O → Ca(OH)₂(slaked lime)

Uses

• Limestone -