Tag: uses of metals and non metals
Questions Related to uses of metals and non metals
Why non-metals have a dull appearance?
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They have many free electrons
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They gain electrons easily
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They do not have lustre
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All of above
Non-metals vary greatly in appearance. They do not have lustre. As it does not have any free electrons light falling on non-metals does not reflect and hence non-metals are not shiny. Hence, they have a very dull appearance.
Which of the following non-metal is hard yet brittle?
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Graphite
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Selenium
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Sulphur
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Diamond
Diamond is the hardest substance known to man with a hardness of 10.0. It is brittle sometimes because it grows in diamond shape crystals, sometimes there are tiny cracks or flaws in the diamond and a hard strike against the crack of course will cause the diamond to crack into many pieces. Crystalline materials have planes of variable shear and normal strengths hence, they fail on fracture mechanism. Also, crystalline nature makes them extremely strong at surface resisting scratch.
Non-metals are:
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soft
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hard
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brittle
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all of above
Non-metals are very brittle and cannot be rolled into wires or pounded into sheets. They break easily when hit by a hammer.
Which type of elements show brittleness?
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Metals
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Non-metals
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Metalloid
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None of the above
Non-metal are neither malleable nor ductile. Non metals are brittle.
Why are non-metals not ductile?
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They are hard
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They are soft
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They are brittle
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All of above
Non-metals are not ductile because they are brittle elements. They break easily. Such non-metals cannot be deformed by a hammer or rolling.
Which of the following is non-ductile?
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Selenium
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Copper
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Aluminium
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Magnesium
Selenium is a chemical element with symbol Se and atomic number 34. It is a nonmetal with properties that are intermediate between those of its periodic table column-adjacent chalcogen elements sulfur and tellurium. As it a non-metal, it cannot be deformed into a wire as it is brittle.
Iodine cannot be deformed into a wire because:
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it is a non-metal
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it is brittle
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both A and B
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none of above
Iodine is a non-metal which is brittle in nature, it breaks and shatters easily when hammered. Hence, it cannot be used to make thin wires and is non-ductile.
Which of the following is not a property of non-metals?
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Non-metals can be stretched into thin wires
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Non-metals are not ductile
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Non-metals are not malleable
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Non-metals break easily
Non-metals are non-malleable and non-ductile. They are brittle. They break easily. So, they are regarded as brittle. They can't be stretched into mines or hammered into sheets.
Brittleness is a characteristic property of:
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gaseous non-metals
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liquid non-metals
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solid non-metals
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none of the above
Brittleness is a characteristic property of non-metals. And here, we consider solid non-metals only. It is not applicable to liquid or gaseous non-metals.
Non-metals do not have lustre which means:
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they do not have a shining surface
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they can't produce sound
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they can't conduct heat
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none of the above
Non metals do not have lustre which means that non-metals do not have a shining surface. That means they have a dull appearance.