Frank Cce Everyday Science Solutions for Class 8 Science Chapter 14 Chemical Effects Of Current are provided here with simple step-by-step explanations. These solutions for Chemical Effects Of Current are extremely popular among class 8 students for Science Chemical Effects Of Current Solutions come handy for quickly completing your homework and preparing for exams. All questions and answers from the Frank Cce Everyday Science Book of class 8 Science Chapter 14 are provided here for you for free. You will also love the ad-free experience on Meritnation’s Frank Cce Everyday Science Solutions. All Frank Cce Everyday Science Solutions for class 8 Science are prepared by experts and are 100% accurate.

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(a) hydrogen and oxygen

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(a) cathode
The object to be electroplated is made the cathode.

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(c) electrorefining
The method of purifying metal by using electricity is called electrorefining.

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(a) cathode
During purification of metal, the refined metal is obtained at cathode.



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Resistance produces hindrance in the flow of current. As the value of resistance increases, the flow of current decreases and vice versa. Hence, to reduce the flow of current, we increase the resistance and to increase the flow of current, we decrease the resistance. Thus, resistance determines the amount of current.

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No, mercury cannot be used as an electrolyte because it is a pure metal. Mercury conducts electricity due to the presence of free electrons in it unlike an electrolyte, which conducts electricity due to ions.

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We should not touch electric appliances with wet hands because wet hands provide path to electric current to flow through our body and we can get an electric shock.

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Iron utensils are electroplated with metals like nickel and zinc to protect them from rusting. After electroplating, durability of iron objects increases.

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LED is a better option for testing the conduction of electricity because LED can glow even with a small value of current. On the other hand, an electric bulb may not glow with a small value of current. Therefore, LED can prove to be a better option for testing the conduction of electricity as compared to an electric bulb.

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(b) a chemical change
During electrolysis, an electrolyte undergoes chemical change.

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(c) distilled water
Distilled water does not allow electricity to pass through it. Therefore, it is a non-electrolyte.

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(c) Sulphuric acid
Sulphuric acid is an electrolyte.

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(b) ammeter
Ammeter is used in electrolysis.

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1. The chemical effect of current involve during transformation of electric energy into chemical energy.
2. During electrolysis, an electrolyte undergoes a chemical change.
3. Electroplating is used for making artificial jewellery.
4. Liquid that conducts electricity are solutions of acids, base and salts.
5. Electrolysis is the process by which an electrolyte is decomposed with the help of electricity.

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1. True

2. True

3. True

4. False
Chemical effect of current involves transformation of electric energy into chemical energy.

5. False
Addition of sodium hydroxide in distilled water makes it an electrolyte.

6. False
Lemon juice conducts electricity.

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Cathode Anode
1. It is negatively charged. 1. It is positively charged.
2. Current enters the electrolyte through this electrode. 2. Current leaves the electrolyte through this electrode.

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Electrolytic solution may be defined as the solution that conducts electricity.

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The process of decomposition of an electrolyte solution, when electricity is passed through it, is called electrolysis.



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Acidulated water is the water that has some amount of acid in it.

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Electrolytic cell is an arrangement of two electrodes (anode and cathode) submerged in an electrolyte.

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Electric current is the amount of electric charge passing through a given point of a conductor in one second.

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Two applications of chemical effect of current:
1. Electroplating
2. Electrorefining

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Bulb consists of a filament that heats up when electricity is passed through it. After heating, it emits light in visible range and the bulb glows.

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Electroplating Electrorefining
1. Electroplating is the process of depositing a thin layer of a metal on a conducting substance. 1. Electrorefining is the process of purifying metals like gold, silver, copper and tin.
2. Electroplating is used for decorative purposes and to protect a metal from corrosion.  2. Electrorefining is used to purify metals.

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Electroplating makes an object look attractive and beautiful by plating an expensive metal over its surface. Thus, after electroplating, a substance can be used for decorative purposes.

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Electrolytes Non-electrolytes
1. An electrolyte solution allows electricity to pass through it. 1. A non-electrolyte solution does not allow electricity to pass through it.
2. Electrolytes contain some amounts of acids, bases or salts. In other words, electrolytes are ionic compounds.
Examples of electrolytes are KCl, NaCl, etc.
2. Non-electrolytes do not have acids, bases or salts, i.e., generally they are covalent compounds.
Examples of non electrolytes are alcohol, kerosene, etc.

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Electrorefining is the process of purifying a metal by using electricity. Electrorefining is a modified form of electrolysis that involves chemical changes.

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Brass objects are protected by electroplating their surfaces with chromium which prevents them from coming in contact with air.

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We can make distilled water a good conductor of electricity by dissolving some amount of acid, base or salt in it.

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Electrorefining is the process of purifying a metal, using electrolysis.
In this process, salt solution of the metal to be purified is taken as an electrolyte solution and the metal to be purified is made anode. A rod of pure metal is made cathode. When current is passed, cations from the anode, start dissolving in the electrolyte and from the electrolyte, they start getting deposited on the cathode. At the end of the process, we obtain pure metal in the form of cathode.

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Electroplating is the process of depositing a thin layer of a metal over another metal or other conductor, to give it a costlier look or make it corrosion resistant, using electrolysis.

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LED (light emitting diode) is an electronic device that emits light when electric current is passed through it. LED is used in an electric circuit to detect the flow of current.

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No, pure water does not conduct electricity. We can add some amount of acid, base or salt in pure water to allow current to flow through it.

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No, it is not safe for an electrician to carry out electric repairs outdoor during rain because rainwater on the body of the electrician can provide a path for electric current to flow through the body, as rainwater is a good conductor of electricity. Due to this, the electrician might get an electric shock.

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Metals can be protected against corrosion by electroplating them with less reactive metals on their surface. For example, iron is protected against corrosion by electroplating of nickel and zinc on its surface. Similarly, brass is protected against corrosion by chromium electroplating.

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Electrolysis is the process of decomposition of an electrolyte into its constituent ions, when electricity is passed through its solution.
Electrolysis could be explained in the following steps:

  1. Two electrodes of a conducting material such as graphite or iron are connected to the opposite terminals of a battery and submerged into a solution of the electrolyte.
  2. When the battery is switched on, the current starts flowing through the solution and the electrolyte dissociates. Cations start moving toward the cathode and anions start moving toward the anode. This brings about a chemical change in the solution and the circuit gets completed due to movement of ions.
  3. The flow of current can be tested by connecting a bulb to the circuit. When we switch on the battery, the bulb glows. This proves that the current flows through the electrolyte.
Following reactions take place during electrolysis of HCl:

At cathode
2H+ + 2e- → H2

At anode
2Cl- → 2e- + Cl2

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Electroplating is the process of coating the surface of a conducting material with a metal to protect it from corrosion or to make it look costlier or smoother.
1. To perform electroplating, the material to be electroplated is washed with an alkali solution so that grease could be removed from its surface.
2. After this, the material is again washed with a dilute acid solution to remove the oxide layer.
3. The cleaned material is then taken as cathode and is submerged into the salt solution of the metal that is to be deposited on the material.
4. Anode is made from the metal whose salt solution is taken as the electrolyte.
5. A complete circuit is made by connecting the battery, rheostat and key as shown in the diagram.
6. When current is passed through the solution, cations of the metal in the solution start depositing on the cathode, i.e., the metal to be electroplated and thus, electroplating of required metal takes place.

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Electrolysis is the process of decomposition of an electrolyte by passing electric current through it.

Electrolysis can be explained as follows:
1. Two electrodes of a conducting material, such as graphite or iron, are connected to the opposite terminals of a battery and submerged into a solution of the electrolyte.
2. When the battery is switched on, the current starts flowing through the solution and the electrolyte dissociates. Cations start moving towards the cathode and anions start moving towards the anode. This brings about a chemical change in the solution and the current flows due to movement of ions through the solution.
3. The flow of current can be tested by connecting a bulb to the circuit. When we switch on the battery, the bulb glows. This proves that current flows through the electrolyte.

Terms involved in electrolysis:

1.  Electrolyte: The solution of the chemical, containing cations and anions, in which the electrodes are submerged, is called electrolyte.
2.  â€‹Electrodes: The rods of a conducting material, connected to the terminals of a battery, are called electrodes. They conduct electricity through the electrolyte. The positive electrode is called anode, whereas the negative electrode is called cathode.

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Chemical effects of electric current may be defined as the chemical changes produced by the electric current when it is passed through an electrolyte. When an electrolyte such as copper sulphate is dissolved in water, it dissociates into positively and negatively charged ions called cation and anion. When electric current is passed through the solution, these ions start moving towards oppositely charged electrodes. This results into a chemical change in the solution.

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Electroplating is the process of coating the surface of an electrode with a metal. It is done by the process called electrolysis. It prevents reactive metals from corrosion. It also makes a metal look better and costlier.

Five examples of electroplated objects:
1. Flower vase
2. Statues
3. Artificial jewellery
4. Utensils
5. Machines

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When an electric current is passed through a wire, it produces a magnetic field. When a compass needle is brought near the current-carrying wire, it gets deflected. This deflection of the compass needle is observed even for a weak flow of electric current. This property of electric current can be used in making an electric tester.

Take the tray from a discarded matchbox and wrap an electric wire four to fives times around it. Place a small compass needle inside the tray of the matchbox. Now, connect one end of the wire to one terminal of a battery and keep the other end of the wire free. Connect a wire to the other terminal of the battery and keep the other end of this wire free as shown in the diagram.



When we connect the two ends (P and Q) of the wire, the compass needle shows deflection. This acts as a tester, which can be used to detect current in a circuit.



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