Acids, alkalis and titrations

• Litmus goes red in acidic solutions and blue in alkaline
• Methyl Orange goes red in acidic solutions and yellow in alkaling
• Phenolphthalein goes colourless in acidic solutions and goes pink in alkaline
• An acid is source of hydrogen ions (H+).
• An alkali is source of hydroxide ions (OH–).
• Alkalis can neutralise acids