Basic Science Solutions for Class 8 Science Chapter 6 Metals And Nonmetals are provided here with simple step-by-step explanations. These solutions for Metals And Nonmetals are extremely popular among class 8 students for Science Metals And Nonmetals Solutions come handy for quickly completing your homework and preparing for exams. All questions and answers from the Basic Science Book of class 8 Science Chapter 6 are provided here for you for free. You will also love the ad-free experience on Meritnation’s Basic Science Solutions. All Basic Science Solutions for class 8 Science are prepared by experts and are 100% accurate.

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Ten examples of metals are potassium (K), iron (Fe), platinum (Pt), tin (Sn), copper (Cu), calcium (Ca), sodium (Na), magnesium (Mg), mercury (Hg) and silver (Ag).

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Metals have a  high tensile strength, i.e., they cannot be broken easily. Example: This property of metals is used to make steel cables for carrying heavy loads.

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(a) We cannot draw wires from a piece of wood or coal because they are brittle. They break down on stretching.
(b) We cannot use nylon or jute ropes for electrical transmission because they are bad conductors of electricity.
(c) We cannot use a cooking utensil made of cardboard because it is a bad conductor of heat and it will start burning itself if kept on fire.

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Hydrogen (H), nitrogen (N), oxygen (O), chlorine (Cl) and argon (Ar) are five non-metals that are gaseous at room temperature.

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Potassium and sodium are two metals that react vigorously with cold water. Magnesium is a metal that continues to burn in steam, if it is ignited.

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Three uses of oxygen:

(a) It is required in all combustion processes.
(b) It is used in the productions of nitric acid and sulphuric acid.
(c) It is used in extraction of metals from their ores.

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Three uses of nitrogen:

(a) It is used by plants for making proteins.
(b) It is used in manufacturing ammonia and urea.
(c) It is used for filling food packets.

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An alloy is a homogenous mixture of metals or metals and non-metals.

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Five physical characteristics of metals are:

(a) They have a high tensile strength; therefore, they cannot be broken down easily.
(b) They are malleable; i.e., they can be beaten into thin sheets.
(c) They are ductile; i.e., they can be stretched into thin wires.
(d) They are good conductors of heat.
(e) They are good conductors of electricity.

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Five physical characteristics of non-metals are:

(a) They are brittle; i.e., they are not flexible.
(b) They are not sonorous.
(c) They have no lustre (except graphite and iodine).
(d) They are bad conductors of heat.
(e) They are bad conductors of electricity.

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Carbon is a non-metal. When it is red-hot, it reacts with steam. This reaction forms a gaseous mixture of carbon monoxide and hydrogen, called water gas. The following reaction occurs:


CCarbon(red hot)+H2OWaterCOWater+H2gas

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Three uses of metals are:

(a) Iron is used for making tools, machines and agricultural equipment because it is very strong, tough and cheap.
(b) Aluminium foil, being light, is used to pack food and medicines.
(c) Mercury is a good conductor of heat and does not stick to glass. Thus, it is used in thermometers.

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Uses of carbon:

(a) Graphite is used in making pencils.
(b) Diamond is used as a gem and for cutting glass and rocks.
(c) Graphite is a good conductor of electricity. Thus, it is used as an electrode.

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Activity series is an ordered arrangement of metals and hydrogen (non-metal) with respect to their activities. The reactivity of a metal decreases down the activity series.
Metals that are placed above hydrogen in the activity series can displace hydrogen from dilute hydrochloric acid and sulphuric acid. Metals that are placed below hydrogen in the activity series cannot displace hydrogen from acids.
Example: Sodium is placed above hydrogen; therefore, it can displace hydrogen from hydrochloric acid. Following reaction occurs:

2NaSodium+2HClHydrochloric acid(dilute)2NaClSodium chloride(colourless)+H2Hydrogen

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Following activity shows that the lead of a pencil conducts electricity and sulphur does not.
Take a pencil and sharpen both its ends. Connect the ends of the pencil to an electric circuit, formed by connecting a bulb to the cell. The bulb glows when pencil is connected to it. This shows that the lead of a pencil conducts electricity. This occurs because lead contains graphite, which is a good conductor of electricity.
Now, replace the pencil with a piece of sulphur. The bulb will stop glowing. This shows that sulphur does not conduct electricity.

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1. Graphite and iodine are lustrous non-metals.
2. All metals are good conductors of heat and electricity.
3. The so-called lead (black part) of a pencil is made of clay and graphite.
4. Though a metal, mercury is a liquid at ordinary temperatures.
5. Argon is used for filling electrical bulbs.
6. Liquid nitrogen is used to preserve donated organs.



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(d) bromine

Bromine is a non-metal that is liquid at ordinary temperatures.

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(d) All of these

All the given options are solid non-metals.

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(a) silver

Silver is the best conductor of electricity.

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(d) all of these

All the mentioned metals are placed above copper in the reactivity series and can replace copper from a solution of copper (II) sulphate.

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(d) neon

Neon is used in advertisement signs.

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Substance Property 1 Property 2
1. Neon A. Metal p. Ductile
B, s B. Non-metal q. Malleable
2. Graphite C. Solid r. Kills germs
B, C, u D. Liquid s. Non-reactive
3. Iodine   t. Cuts glass
B, C, r   u. Conducts electricity
4. Aluminium    
A, C, p, q, u    
5. Diamond    
B, C, t    
6. Mercury    
A, D, s    



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