When elements combine to form compounds, there are two major types of bonding that can result. Ionic bonds form when there is a transfer of electrons from one species to another, producing charged ions which attract each other very strongly by electrostatic interactions, and covalent bonds , which result when atoms share electrons to produce neutral molecules.
In general, metal and nonmetals combine to form ionic compounds , while nonmetals combine with other nonmetals to form covalent compounds molecules. Since the metals are further to the left on the periodic table, they have low ionization energies and low electron affinities , so they lose electrons relatively easily and gain them with difficulty.
They also have relatively few valence electrons, and can form ions and thereby satisfy the octet rule more easily by losing their valence electrons to form positively charged cations. Nonmetals are further to the right on the periodic table, and have high ionization energies and high electron affinities , so they gain electrons relatively easily, and lose them with difficulty.
They also have a larger number of valence electrons, and are already close to having a complete octet of eight electrons. The nonmetals gain electrons until they have the same number of electrons as the nearest noble gas Group 8A , forming negatively charged anions which have charges that are the group number minus eight.
That is, the Group 7A nonmetals form 1- charges, the Group 6A nonmetals form 2- charges, and the Group 5A metals form 3- charges. The Group 8A elements already have eight electrons in their valence shells, and have little tendency to either gain or lose electrons, and do not readily form ionic or molecular compounds. Ionic compounds are held together in a regular array called a crystal lattice by the attractive forces between the oppositely charged cations and anions. These attractive forces are very strong, and most ionic compounds therefore have very high melting points.
Metals typically have a high conductivity and low ionization energy. Metalloids are intermediate between metals and nonmetals. Nonmetals have low conductivity of electricity and heat and high ionization energy. Metals have a high heat conductivity. Metalloids have an intermediate capacity to conduct heat, while nonmetals are poor heat conductors.
Metals have a low ionization energy. Metalloids have intermediate ionization levels and nonmetals have high ionization energies. High electrical conductivity is a feature of metals while metalloids can conduct electricity under certain conditions only. Nonmetals are poor conductors of electricity. Examples of metals include copper, tin, and zinc. Silicon, boron, and arsenic are examples of metalloids, and oxygen, carbon, and hydrogen are examples of nonmetals.
Metals have properties such as high conductivity and low electronegativity while nonmetals have the reverse. Metalloids are intermediate in properties between both the metals and nonmetals, while noble gases are elements that occur only in a gas form; while the other substances can take on more than one form.
Metals are very malleable, can conduct electricity and heat and have low ionization energy, while nonmetals are brittle, do not conduct electricity or heat well and have a high ionization energy.
Metalloids do not have all the features that metals have, even though some metalloids do conduct electricity at times. Metals always can conduct electricity, are very malleable and have a high heat conductivity. Difference Between Metals, Metalloids, and Nonmetals.
Difference Between Similar Terms and Objects. MLA 8 Osborn, Dr. Name required. Email required. Please note: comment moderation is enabled and may delay your comment. Metalloids--these are the elements which show properties of metals as well as of non-metals.
Related questions How are metalloids different from metals? How many nonmetals are there in the periodic table? Why are metalloids described as semiconductors?
Why metals are good conductors of electricity? Why are metals malleable?
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