Stomach acid turns universal indicator paper a ... Use the colour comparison chart to find the pH of your substances. If the different samples changed the colour the way you expected, then that ...

Kits (pH) containing the necessary chemicals and color charts are available from garden stores ... Most minerals and nutrients are more soluble or available in acid soils than in neutral or slightly ...

Use a measuring cylinder to add dilute hydrochloric acid to a beaker ... Wait 30 seconds, then match the colour to a pH colour chart. Record the estimated pH. Add a level spatula of calcium ...