#21 - Acids and Alkalis

Edexcel IGCSE Chemistry - The Companion Audio Guide

Learn about acids and alkalis: acids release hydrogen ions (H⁺), while alkalis release hydroxide ions (OH⁻). Indicators like litmus, phenolphthalein, and methyl orange help distinguish between them. The pH scale classifies solutions from acidic to alkaline, with neutralization reactions forming water when acids and alkalis mix.