Tag: uses of metals and non metals
Questions Related to uses of metals and non metals
Which of the following are uses of sulphur?
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Sulphur is used in preparation of conducting wires
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A mixture of zinc and sulphur on heating with sulphur produces a greyish residue of zinc sulphide
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Sulphur is an element belonging to VI A group
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Sulphur is a nonmetallic element.
Zinc on heating with sulphur produces a greyish residue of zinc sulphide.
Sulphur is an element belonging to VI A group.
Sulphur is a nonmetallic element.
Plastic sulfur has no sharp melting point.
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True
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False
Amorphous or plastic sulfur is produced by rapid cooling of molten sulfur e.g. by pouring it in cold water. It has helical form and metastable at room temperature reverting to its crystal allotrope and have sharp melting point.
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True
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False
In case of iodine, the large size of the atom results in low shielding of valence electrons.
The sparkling shine of the diamond comes from its cut, clarity, refractive index and reflection.
Therefore Diamond , graphite & iodine are nonmetals which are lustrous because of their crystal structure.
Therefore, option A is correct.
Compare the physical properties of metals and non-metals in general with reference to melting point.
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Both have low melting point
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Both have high melting point
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Metals have low melting point while non-metals have high melting point
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Metals have high melting point and non-metals have low melting point
Metals have high melting and boiling point. Tungsten has the highest melting point where as silver has low boiling point. Sodium and potassium have low melting points. Non metals have low melting point.
Diamond and graphite are good conductors of electricity.
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True
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False
Graphite is able to conduct electricity, due to delocalization of the pi bond electrons above and below the planes of the carbon atoms. These electrons are free to move, so are able to conduct electricity.
In diamond, all four outer electrons of each carbon atom are 'localized' between the atoms in covalent bonding. The movement of electrons is restricted and diamond does not conduct an electric current.
Thus, graphite is a good conductor and diamond is not.
Option "B" is correct.
Which of the following is a good conductor of electricity?
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Diamond
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Graphite
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Both A and B
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None of the above
Diamond and graphite are allotropes of carbon. Graphite has carbon molecules held together by weak van der Waal's forces of attraction and they have loosely bound electrons which are responsible for conducting electricity, while diamond is the hardest and strongest material in which all the molecules are bound by strong bonding between carbon tetrahedrons held by strong forces of attraction and so, they do not have free or loosely bound electrons to conduct electricity.
By dropping a drop of water on a glowing electric bulb, it bursts. This is because glass is a _________.
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good conductor of heat
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bad conductor of heat
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transparent substance
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good conductor of electricity
1) The glass is actually an insulator.
2) It doesn't allow the flow of electrons easily from atom to atom, as seen in substances like copper, and other metals which are excellent conductors of both heat and electricity.
3) Insulators have electrons that are held tightly which means they aren't shared between other atoms.
Which of the following is a property of nonmetals?
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Low densities
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Low melting points
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Poor conductor of electricity
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All the three
Which of the following are properties of non-metals?
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Low melting point
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Poor conductor of electricity
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Low densities
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All of these
- High ionization energies.
- High electronegativities.
- Poor thermal conductors.
- Poor electrical conductors.
- Brittle solids - not malleable or ductile.
- Little or no metallic lustre.
- Gain electrons easily.
- Dull, not metallic-shiny, although they may be colorful.
- Low melting point and densities.
- Lower melting points and boiling point than the metals.
The non-metal having shining surface is:
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sulphur
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phosphorus
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iodine
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carbon
It's because going down the group the size of the atom increases because of the shielding effect due to which the interaction between the atom and the outermost electron decreases.
So these electrons on the surface of iodine become excited by absorbing heat energy from light. so when they release this energy and come to their normal state, they emit this light so it appears that they have a shining surface.
So, the correct option is $C$