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Water’s unique properties make it a powerful solvent, allowing it to dissolve many substances and form solutions. These solutions can conduct electricity if they contain electrolytes—solutes that break into charged particles in water. Using a conductivity tester, we can see that soluble substances like salt allow electricity to flow, while insoluble ones do not.

00:00 Why does the bulb glow sometimes?
00:35 Homogeneous & heterogeneous mixtures (recap)
01:47 What are electrolytes?
02:35 Are all solutions electrolytes?
03:37 What are weak electrolytes?
04:06 Revisiting the experiment: Electrolyte or not
05:40 Summary

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