Non metal which has metallic luster

Download PDFs. Quick Revision Notes. Mind Maps. Sample Question Papers. Previous Years Papers. Important Questions. Supplementary Books. SnapSolve Tutor. Follow us on Youtube. Follow us on Facebook. Download APP. About SnapSolve. Join Now. Question Chemistry Class Iodine is a non-metal which has metallic luster.

A True B False. Hint: We know that iodine is non-metal from the halogen group. And Iodine is a p-block 17th group and 5th period element. It exists in gaseous form. Step by step solution: Iodine is an intensely colored solid with an almost metallic luster. This solid is relatively volatile and it sublimes when heated to form a violet-colored gas. This metallic lustre is because going down in the 17th group the size of the atom increases because of shielding effect due to which the interaction between the atom and the outermost electron of the atom decreases, and outermost electrons are loosely bound, so the electrons on the surface of iodine become excited by absorbing heat energy from light.

When they release this energy and come to their normal state, they emit this light so it appears that they have a lustrous surface. This happens only in iodine halogen not in others. It features highly concentrated pigments and boasts an opaque coverage with only one coat. Metallic Lustre adheres to most absorbent surfaces, as well as metal. Note: Graphite is also a non-metal which has metallic lusture. Metallic luster is due to presence of free electrons in them generally non metals don't exhibit this property, but iodine and graphite are non metals they exhibit metallic luster.

Correct Malleability: Metals have the ability to withstand hammering and can be made into thin sheets known as foils a sugar cube chunk of gold can be pounded into a thin sheet which will cover a football field.

Ductility: Metals can be drawn into wires. Hardness: All metals are hard except sodium and potassium, which are soft and can be cut with a knife. Valency: Metals have 1 to 3 electrons in the outermost shell of their atoms.

Conduction : Metals are good conductors because they have free electrons. Silver and copper are the two best conductors of heat and electricity. Lead is the poorest conductor of heat. Bismuth, mercury and iron are also poor conductors Density : Metals have high density and are very heavy.

Iridium and osmium have the highest densities where as lithium has the lowest density. Melting and Boiling Points : 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. Chemical Properties of Metals Metals are electropositive elements that generally form basic or amphoteric oxides with oxygen.

Other chemical properties include: Electropositive Character : Metals tend to have low ionization energies, and typically lose electrons i. Example Would you expect it to be solid, liquid or gas at room temp? Solutions Oxides of metals are characteristically solid at room temp. Nonmetals Elements that tend to gain electrons to form anions during chemical reactions are called non-metals. Physical Properties of nonmetals: Physical State : Most of the non-metals exist in two of the three states of matter at room temperature: gases oxygen and solids carbon.

Non-Malleable and Ductile : Non-metals are very brittle, and cannot be rolled into wires or pounded into sheets. Conduction : They are poor conductors of heat and electricity. Luster: These have no metallic luster and do not reflect light Conductivity : Poor conductors of heat and electricity Melting and Boiling Points : The melting points of non-metals are generally lower than metals Seven non-metals exist under standard conditions as diatomic molecules : H 2 g N 2 g O 2 g F 2 g Cl 2 g Br 2 l I 2 l volatile liquid - evaporates readily.

Chemical Properties of Nonmetals Non-metals have a tendency to gain or share electrons with other atoms. They are electronegative in character. Metalloids Properties intermediate between the metals and nonmetals. Conduction : Some metalloids, such as silicon and germanium, can act as electrical conductors under the right conditions, thus they are called semi-conductors.

Solid Solutions : They can form alloys with other metals. Chemical Properties of Metalloids Their physical properties tend to be metallic, but their chemical properties tend to be non-metallic. Trends in Metallic and Nonmetallic Character Metallic character is strongest for the elements in the leftmost part of the periodic table, and tends to decrease as we move to the right in any period nonmetallic character increases with increasing ionization values.

Distinguishing luster shine. Non-lustrous, various colors. Malleable and ductile flexible as solids. Brittle, hard or soft. Conduct heat and electricity. Poor conductors.