Acid–alkali titration sim
25.0 cm³ of sodium hydroxide was pipetted into the flask with three drops of methyl orange, which is yellow in alkali.
Acid–alkali titration · covers the GCSE, IGCSE, O-Level topic
What the sim shows
25.0 cm³ of sodium hydroxide was pipetted into the flask with three drops of methyl orange, which is yellow in alkali. The burette holds 0.100 mol/dm³ hydrochloric acid. Each drop is about 0.05 cm³. Where a drop lands the indicator flashes orange, and the flash lasts longer as the end point nears: then go drop by drop, swirling. Stop at the first orange colour that stays. The titre is the final reading minus the first one. Read the bottom of the meniscus at eye level, to the nearest 0.05 cm³ (right). From the titre, find the concentration of the sodium hydroxide.
- Methyl orange: yellow in alkali, orange at the end point, red in acid
- Right: the meniscus close up, at eye level
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