Exercises

11.7 Exercises

Description

Quick Overview

This section covers the chemical effects of electric current and explores the conduction properties of different liquids.

Standard

In this section, the text discusses how electric current interacts with various materials, particularly focusing on liquids. It examines how some liquids are good conductors of electricity, while others are poor conductors, using various experiments and activities as examples.

Detailed

Chemical Effects of Electric Current

In this section, we delve into the chemical effects caused by electric current, specifically focusing on the conduction properties of different liquids. We learn about conductors and insulators, and the importance of testing various substances to ascertain their ability to conduct electricity. The section begins by discussing solid conductors like copper and aluminum, and transitions into testing liquids using a simple electric tester with a battery. Through a series of experiments, we find that most liquids that conduct electricity are solutions of acids, bases, and salts.

Furthermore, it is essential to distinguish between good and poor conductors. For instance, liquids such as lemon juice and vinegar are identified as good conductors, while distilled water is noted as a poor conductor until an ionic substance, such as salt, is dissolved. The text also explains that when electric current passes through these conducting solutions, it may cause chemical reactions, leading to observable changes like gas formation and color changes. This understanding lays the groundwork for the concept of electroplating, where unwanted metals are coated with a layer of another metal through electrical methods. Overall, this section emphasizes the practical implications of electric currents and their vital role in chemical processes.

Key Concepts

  • Conductors vs Insulators: Conductors allow electricity, while insulators do not.

  • Testing Liquid Conductivity: Liquids can be tested for conductivity using a simple electric tester.

  • Chemical Effects of Current: Passing current through solutions can lead to chemical reactions, such as gas production.

  • Electroplating: The process of depositing a layer of metal onto another material through electrical means.

Memory Aids

🎵 Rhymes Time

  • Lemon juice and vinegar too, conduct electricity, it's true!

📖 Fascinating Stories

  • Once a lemon and a banana wanted to race in a circuit. The lemon glowed bright with electricity, showing it was a good conductor, while the banana stood still, knowing it couldn't pass the tests of the current.

🧠 Other Memory Gems

  • GACE: Gas And Color Effects for the changes we see when current flows.

🎯 Super Acronyms

DESS

  • Durable External Shiny Surface reminds us electroplating provides protective coatings.

Examples

  • Lemon juice conducts electricity, which is why it glows a tester bulb.

  • Water may not conduct electricity, but adding salt makes it a conductor.

  • Electroplating is used to coat iron with zinc to prevent corrosion.

Glossary of Terms

  • Term: Conductors

    Definition:

    Materials that allow electric current to flow through them easily.

  • Term: Insulators

    Definition:

    Materials that do not allow electric current to flow through them.

  • Term: Electroplating

    Definition:

    The process of depositing a layer of metal onto another material using electric current.

  • Term: Good Conductor

    Definition:

    A substance that allows electricity to pass through with minimal resistance.

  • Term: Poor Conductor

    Definition:

    A substance that does not allow electricity to pass through easily.

  • Term: Electrode

    Definition:

    The conductor through which electricity enters or leaves an electrolyte solution.