Class 8 Science Chemical Effects of Electric Current
If you are looking for Class 8 Science Chemical Effects of Electric Current extra question answers , then you are at the right place.
Q: What makes water a good conductor of electricity?
A: The presence of dissolved salts and minerals makes water a good conductor. Distilled water, which is free of salts, is a poor conductor of electricity.
Q: Why is it dangerous to touch electrical appliances with wet hands?
A: Water containing dissolved salts is a good conductor of electricity, so wet hands can complete an electrical circuit and cause electric shock.
Q: What is an electrode?
A: An electrode is a rod or plate used to conduct electricity into or out of a solution during electrolysis, typically connected to the terminals of a battery.
Q: What are the chemical effects of electric current?
A: The chemical effects include:
Formation of gas bubbles
Deposits of metal on electrodes
Changes in solution color
Chemical reactions in the conducting solution
Q: What is electroplating?
A: Electroplating is the process of depositing a thin layer of one metal onto another material using electricity, typically to improve appearance or protect the underlying metal.
Q: Who discovered the chemical effects of electric current in water?
A: William Nicholson, a British chemist, demonstrated in 1800 that passing current through water produces oxygen and hydrogen bubbles.
Q: How can you test if a liquid conducts electricity?
A: You can use a tester with a bulb or LED, or use a magnetic compass to check for current flow when the tester’s ends are dipped into the liquid.
Q: What happens when salt is added to distilled water?
A: Adding salt to distilled water makes it a good conductor of electricity, as the dissolved salt provides ions that can carry electric current.
Q: What are some common applications of electroplating?
A: Electroplating is used for:
Coating bicycle parts with chromium
Creating gold or silver-looking jewelry
Protecting iron from corrosion by coating with zinc
Making tin-coated food cans
