Test: Chemical Effects Of Electric Current - 3


20 Questions MCQ Test Science Class 8 | Test: Chemical Effects Of Electric Current - 3


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This mock test of Test: Chemical Effects Of Electric Current - 3 for Class 8 helps you for every Class 8 entrance exam. This contains 20 Multiple Choice Questions for Class 8 Test: Chemical Effects Of Electric Current - 3 (mcq) to study with solutions a complete question bank. The solved questions answers in this Test: Chemical Effects Of Electric Current - 3 quiz give you a good mix of easy questions and tough questions. Class 8 students definitely take this Test: Chemical Effects Of Electric Current - 3 exercise for a better result in the exam. You can find other Test: Chemical Effects Of Electric Current - 3 extra questions, long questions & short questions for Class 8 on EduRev as well by searching above.
QUESTION: 1

What is current?

Solution:

Current is the flow of charge.

QUESTION: 2

In electrolytic solutions, which of the following acts as carrier of charge?

Solution:

In electrolytic solutions, electrolyte splits into positive and negative ions. The charge is moved through ions.

QUESTION: 3

What are insulators?

Solution:

Insulators are substances that do not conduct electricity.

QUESTION: 4

Which of the following is an insulator?

Solution:

Wood is an insulator while iron, graphite and silver are good conductors of electricity.

QUESTION: 5

Which of the following circuits gives the correct way of connecting an LED to light it up?

Solution:

An LED has two leads. One lead is slightly longer than the other. The longer lead is always connected to a positive terminal of the battery while the shorter lead is always connected to a negative terminal of the battery. In circuit (B) switch is present and is in its ON position. Only this makes the LED glow.

QUESTION: 6

Which of the following energy conversions takes place in a cell?

Solution:

In a cell, chemical energy is converted into electrical energy.

QUESTION: 7

Which of the following are the characteristics of an electrolyte?

Solution:

The characteristic of an electrolyte is that it should be able to form positive and negative ions.

QUESTION: 8

Which acid is present in lemon juice that acts as an electrolyte?

Solution:

Citric acid is present in the lemon juice which acts as an electrolyte.

QUESTION: 9

Which of the following is the electrolyte in a dry cell?

Solution:

The electrolyte in a dry cell is ammonium chloride.

QUESTION: 10

In a dry cell, which of the following acts as the positive terminal?

Solution:

In a dry cell, metal cap on the carbon rod acts as a positive terminal.

QUESTION: 11

What is the common voltage produced by a dry cell?

Solution:

The common dry cell produces a voltage of 1.5 V

QUESTION: 12

What happens when electric current is made to flow through a conductor?

Solution:

When electric current flows through a conductor, some amount of electrical energy is converted into heat energy.

QUESTION: 13

Nichrome is an alloy. Which of the following metals make up this alloy?

Solution:

Nichrome is an alloy of nickel and chromium.

QUESTION: 14

What is the splitting of a compound using electricity called?

Solution:

Electrolysis is the splitting of a compound using electricity.

QUESTION: 15

What is the principle involved in the glowing of an electric bulb?

Solution:

Due to the heating effect of current, the filament of the bulb gets heated to a high temperature and it starts glowing.

QUESTION: 16

Why are LEDs extensively used to replace bulbs?
(i) Consume less electricity
(ii) Have longer life
(iii) Have more power

Solution:

LEDs are extensively used to replace bulbs because they consume less electricity, have longer life and have more power.

QUESTION: 17

Which of the following is the best conductor of electricity?

Solution:

Sea water is saline and so, it is a good conductor of electricity.

QUESTION: 18

Which of the following effects of current is responsible for the deflection of a compass needle in an electric field?

Solution:

Magnetic effect of current is responsible for the deflection of a compass needle in an electric field.

QUESTION: 19

Which of these is the industrial applications of the chemical effects of electric current?

Solution:

Electroplating is the most common industrial application of chemical effects of electric current as are galvanizing and anodizing.

QUESTION: 20

Which of the following liquids is a bad conductor of electricity?

Solution:

Distilled water or pure water is a bad conductor of electricity.