WBBSE Chapter 2 Element Compound And Chemical Reaction Chemical Effects Of Electricity VSAQs
Question 1. Name one metallic conductor and one non-metallic conductor of electricity.
Answer:
One metallic conductor of electricity is copper and one non-metallic conductor of electricity is graphite.
Question 2. What is responsible for the conduction of electricity within metal?
Answer:
The electron is responsible for the conduction of electricity within the metal.
Question 3. What is responsible for the conduction of electricity within an aqueous solution of an electrolyte?
Answer:
Positively charged cations and negatively charged anions are responsible for the conduction of electricity within an electrolyte.
Question 4. Name one substance which is a liquid and conducts electricity but is not an electrolyte.
Answer:
Mercury is a metal which is liquid and conducts electricity but it is not an electrolyte.
Question 5. Name two strong electrolytes.
Answer:
Strong Electrolytes:
Potassium chloride (KCI) and sodium hydroxide (NaOH) are examples of strong electrolytes.
WBBSE Class 8 Chemical effects of electricity very short answer questions
Question 6. Name two weak electrolytes.
Answer:
Weak Electrolytes:
Acetic acid (CH3COOH) and ammonium hydroxide (NHFlH) are examples of weak electrolytes.
Read And Learn More WBBSE Solutions For Class 8 School Science Very Short Answer Type Questions
Question 7. Name one bad conductor of electricity.
Answer:
Bad Conductor of electricity:
A piece of wood or a piece of rubber is an example of a bad conductor of electricity.
Question 8. Which elements are obtained at the anode and cathode when fused sodium chloride is electrolysed?
Answer:
Sodium (Na) at the cathode and chlorine (Cl2) at the anode.
Question 9. During electrolysis of acidified water, what are the substances obtained at the cathode (made of platinum) and anode (made of platinum)?
Answer:
During the electrolysis of acidified water, hydrogen gas is formed at the platinum cathode and oxygen gas and water are formed at the platinum anode.
WBBSE Solutions for Class 8 Science
Question 10. Name one substance which is soluble in water but its aqueous solution is a bad conductor of electricity.
Answer:
Ethyl alcohol or methyl alcohol are both soluble in water but their aqueous solutions do not conduct electricity.
Question 11. During the electroplating of copper, what is used as an electrolyte solution?
Answer:
During the electroplating of copper, an aqueous solution of copper sulphate in which a few drops of sulphuric acid are added, is used as the electrolyte solution.
Question 12. What is meant by anode?
Answer:
Anode:
Anode is the electrode which is connected to the positive terminal of the battery.
Chemical Effects of Electricity Class 8 Very Short Questions
Question 13. What is meant by cathode?
Answer:
Cathode:
The cathode is the electrode which is connected to the negative terminal of the battery.
Question 14. During electrolysis, which energy is converted into which energy?
Answer:
During electrolysis, electrical energy is converted to chemical energy.
Question 15. Mention some uses of electrolysis.
Answer:
Some Uses Of Electrolysis:
The electrolysis process is used for metal extraction, purification of metal and electroplating.
Question 16. Mention what is used as cathode and anode during the electroplating of copper.
Answer:
During the electroplating Of copper, a pure copper bar is used as an anode and the articles to be coated with copper are used as cathode.
WBBSE Class 8 Science Chapter 2
Question 17. What is galvanization?
Answer:
Galvanization:
The process of coating a layer of zinc on the surface of another material is called galvanization.
WBBSE Chapter 2 chemical effects of electricity answers
Question 18. What are the cations and anions that develop in the aqueous solution of zinc phosphate?
Answer:
⇒ \(Zinc Phosphate \left[\mathrm{Zn} n_3\left(\mathrm{PO}_4\right)_2\right] \rightleftharpoons 3 \mathrm{Zn}^{2+}+2\left(\mathrm{PO}_4\right)^{2-} Cation Anion\)
Question 19. Name the electrolytic cell used for the electrolysis of acidulated water.
Answer:
Hoffmann’s voltameter
Class 8 Chemical Effects of Electricity Questions
Question 20. Which one is a strong electrolyte: tap water or sea water?
Answer:
Since seawater contains more dissolved salts, therefore, seawater is a strong electrolyte compared to tap water.
Question 21. What is electrolysis?
Answer:
Electrolysis:
The chemical decomposition produced by passing an electric current through an electrolyte (in solution or in molten state) is called electrolysis.
Question 22. Acidified water is electrolysed using carbon electrodes. What is produced at the positive carbon electrode and negative carbon electrode?
Answer:
- Positive carbon electrode: oxygen gas
- Negative carbon electrode: Hydrogen gas
Chemical effects of electricity concepts with very short answers for Class 8
Class 8 Science Elements Compounds and Chemical Reactions
Question 23. How does the degree of ionization of an electrolyte vary with temperature?
Answer:
The extent of dissociation increases with the increase in temperature and vice versa.
Question 24. Which one is an electrolyte: A solid crystal of sodium chloride, liquid hydrogen chloride, a dilute aqueous solution of acetic acid, or pure and dry concentrated sulphuric acid?
Answer:
Dilute an aqueous solution of acetic acid.