Poor Conductors | Chemistry

Summary

This video explains the concept of electrical conductivity through engaging experiments. It demonstrates that air is a poor conductor under normal conditions, while distilled water does not conduct electricity due to its purity. However, adding salt to water allows it to conduct electricity. The video further explores the conductivity of different solutions, showing that hydrochloric acid and caustic soda conduct electricity, while sugar solution does not. The experiments emphasize the importance of understanding conductivity for safety, particularly when handling electrical appliances around water.

Takeaways

• ⚡ Electricity can be conducted by certain substances, which can be tested using a simple circuit with a battery and a magnetic needle.
• 🌬️ Air is a poor conductor of electricity under normal conditions, as demonstrated by the lack of deflection in the needle.
• ⚡ However, air can conduct electricity during lightning, highlighting its dual nature as a poor conductor rather than an insulator.
• 💧 Distilled water (pure H2O) does not conduct electricity, indicating the importance of impurities in electrical conductivity.
• 🧂 Adding salt to distilled water allows the solution to conduct electricity, demonstrating how minerals influence conductivity.
• 🌊 Natural water sources like tap water and well water conduct electricity due to dissolved mineral salts, posing safety risks when wet.
• 🔬 Testing various solutions reveals that salt, acids, and bases can conduct electricity effectively.
• 🧪 Dilute hydrochloric acid is a good conductor of electricity, as evidenced by needle deflection during testing.
• 🔋 Caustic soda solution also conducts electricity, confirming that many bases are effective conductors.
• 🍬 Sugar solution does not conduct electricity, showing that not all dissolved substances result in conductivity.

Q & A

What is the purpose of the electrical tester in the experiment?

The electrical tester is used to determine whether a substance conducts electricity by measuring deflection in a magnetic needle connected to a circuit.

What does it indicate if the magnetic needle shows deflection when testing a substance?

If the magnetic needle shows deflection, it indicates that the substance being tested conducts electricity.

Why is air considered a poor conductor of electricity under normal conditions?

Air is considered a poor conductor because it does not allow electricity to pass through it under normal conditions, as evidenced by no deflection in the tester's needle.

What happens to the conductivity of distilled water when salt is added?

When salt is added to distilled water, it becomes conductive, as indicated by the deflection of the magnetic needle, showing that salt solutions can conduct electricity.

How does the conductivity of tap water compare to distilled water?

Tap water conducts electricity due to the presence of mineral salts dissolved in it, whereas distilled water, being pure H₂O, does not conduct electricity.

What is the significance of classifying substances as good conductors and poor conductors?

This classification helps to understand how different substances interact with electricity, as some can conduct well while others do so poorly or not at all, without labeling them strictly as conductors or insulators.

What results were observed when testing hydrochloric acid and caustic soda solutions?

Both hydrochloric acid and caustic soda solutions conducted electricity, as indicated by the deflection of the needle when tested.

Why doesn't sugar solution conduct electricity?

Sugar does not dissociate into ions in solution, which is necessary for conducting electricity; thus, sugar solution does not show any deflection in the tester.

What safety precautions should be taken when using electrical appliances around water?

One should be cautious not to touch electrical appliances with wet hands or while standing on a wet surface, as water can conduct electricity, posing a risk of electric shock.

Can air conduct electricity in specific circumstances?

Yes, air can conduct electricity under specific circumstances, such as during lightning, which is why it is classified as a poor conductor rather than a complete insulator.