Ideal for basic science/chemistry labs. They're affordable too. I am a high school science teacher and also homeschool with my eldest son (due to an autoimmune disease). He used them for a chemistry problem and they did exactly what they were supposed to. If your strips show no significant changes, it is most likely due to similar/low pH levels. Try many more acidic substances and mixtures (vinegar/OJ/etc) and you will see the difference.
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