The elements can be classified as metals, nonmetals, or semimetals (metalloids).
Metals are good conductors of heat and electricity, and are malleable (they can be swaged into sheets) and ductile (they can be drawn into wire). Most metals are solids at room temperature with a characteristic silvery luster (with the exception of mercury, which is a liquid).
Nonmetals are (usually) poor conductors of heat and electricity and are not malleable or ductile; Many of the elementary nonmetals are gases at room temperature, others are liquids, and others are solids.
The metalloids are intermediate in their properties. In their physical properties, they are more similar to nonmetals, but under certain circumstances, some of them can be made to conduct electricity. These semiconductors are extremely important in computers and other electronic devices.
Many periodic tables along the right side of the table separate metals from nonmetals. The metals are to the left of the line (except for hydrogen, which is a nonmetal), the nonmetals are to the right of the line, and the elements immediately adjacent to the line are the metalloids.
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 that 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).
Metals in the periodic table
Most elements on the periodic table are metals. They are grouped together in the middle to the left-hand side of the periodic table. The metals consist of alkali metals, alkaline earth, transition metals, lanthanides, and actinides.
More Resource: What is Metal and Their Types?
The alkali metals can be found in the first column on the left side of the Periodic Table. They are soft metals that are highly reactive and have one electron in their outermost s sub-shell.
The six alkali metals are: Lithium, Sodium, Potassium, Rubidium, Lepidolite Mineral Source for Rubidium, and Caesium, Caesium, Francium.
Alkaline Earth Metals
The alkaline earth metals are found in column 2 on the left side of the Periodic Table. They are generally harder and denser than alkali metals, have 2 electrons in their outermost s sub-shell, and each makes a distinct color in their flames.
The six alkaline earth metals are: Beryllium, Magnesium, Calcium, Strontium, Barium, Radium.
The transition metals are found in the center of the main body of the Periodic Table. They are sometimes called heavy metals and are denser than alkali or alkaline earth metals.
There are 38 transition metals including: Cobalt, Copper, Native copper from Arizona, Gold, Iron, Mercury, Platinum, Silver, Titanium, Tungsten, Zinc.
Rare Earth Metals
The rare earth metals are typically found in their own table below the main Periodic Table. However, they actually fit into the middle of the Periodic Table. There are two types of rare-earth metals: Lanthanides and Actinides.
There are 15 lanthanides listed on the Periodic Table. All of these elements are so similar, it is very difficult to differentiate them.
Examples of lanthanides include: Cerium, Promethium, Gadolinium, Dysprosium, Lutetium.
There are 15 actinides listed in the Periodic Table. Most of these do not occur in nature because they are so unstable but are produced in nuclear reactors and particle accelerators.
Examples of actinides include: Thorium, Uranium, Plutonium, Californium, Mendelevium
Metals listed as other metals are found toward the right side of the main body of the Periodic Table. These are sometimes called semimetals and sometimes called post-transition metals. They are typically softer than other metals and have lower melting points.
Scientists don’t agree universally on which elements belong in this category, so depending on the table you’re looking at, there might be anywhere from 8-14.
Examples of other metals include: Aluminum, Bismuth, Bismuth crystal, Indium, Lead, Tin.
Properties of Metals
Metals are elements that form positive ions by losing electrons during chemical reactions, except hydrogen. Thus, they are electropositive elements with low ionization energies. Most metals share the properties of being shiny, very dense, and having high melting points. Furthermore, they are ductile, malleable, and lustrous. Metals are also good conductors of heat and electricity. All metals are solids at room temperature, except mercury which is a liquid.
Metals generally form ionic bonds with nonmetals, but there are exceptions. Most metals form at least one basic oxide, although some are amphoteric. Metals exhibit a wide range of reactivity. Special groups of metals include the noble metals Ru, Rh, Pd, Pt, Au, Os, Ir, Ag, and the refractory metals Nb, Mo, Ta, W, and Re.
Physical Properties of Metals:
Some of the main physical properties of metals are given below.
- Metals are malleable, in their solid-state and they can be hammered into thin sheets. Gold is the most malleable of all the metals
- Metals are ductile, which means they can be drawn into a wire. Silver is one of the most ductile metals.
- Metals are a good conductor of heat and electricity.
- Metals are lustrous, which means they have a shiny appearance. Some metals will form a patina and the luster is lost.
- Metals have high tensile strength. It means they can hold heavyweights.
- Metals are sonorous. It means when we strike them, they make a ringing sound.
- Metals are hard. It means they cannot be cut easily.
- Forming cations in an aqueous solution by losing their electrons
- The melting point of metals: Metals often have high melting and boiling points, but there are many exceptions to the melting point, like cesium, gallium, mercury, rubidium, and tin which all have fairly low melting points. However, most boiling points are still quite high.
- Metals exhibit a wide range of densities, but generally are denser than nonmetals. Tungsten, platinum, osmium, gold, and iridium are extremely dense.
- Most metals are silvery, although some like gold, cesium, and copper are colored.
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.e. are oxidized) when they undergo chemical reactions They normally do not accept electrons. For example:
- Alkali metals are always 1+ (lose the electron in s subshell)
- Alkaline earth metals are always 2+ (lose both electrons in s subshell)
- Transition metal ions do not follow an obvious pattern, 2+ is common (lose both electrons in s subshell), and 1+ and 3+ are also observed
Compounds of metals with non-metals tend to be ionic in nature. Most metal oxides are basic oxides and dissolve in water to form metal hydroxides:
Metal oxides exhibit their basic chemical nature by reacting with acids to form metal salts and water:
Location of Metals on the Periodic Table
Over 75% of the elements are metals, so they fill most of the periodic table. Metals are on the left side of the table. The two rows of elements below the main body of the table (the lanthanides and actinides) are metals.
In the periodic table, you can see a stair-stepped line starting at Boron (B), atomic number 5, and going all the way down to Polonium (Po), atomic number 84. Except for Germanium (Ge) and Antimony (Sb), all the elements to the left of that line can be classified as metals.
Uses of Metals
Metals find use in every aspect of life. Here is a list of some of their uses:
- Structural components
- Wires and electrical appliances
- Heat sinks
- Nutrition (iron, copper, cobalt, nickel, zinc, molybdenum)
Nonmetals In Periodic Table
The nonmetal elements occupy the upper right-hand corner of the periodic table. Nonmetals include the nonmetal group, the halogens, and the noble gases. These elements have similar chemical properties to each other that distinguish them from the elements that are considered metals.
Groups of Nonmetals
The nonmetal element group is a subset of the nonmetals. The nonmetal element group consists of hydrogen, carbon, nitrogen, oxygen, phosphorus, sulfur, and selenium. Hydrogen acts as a nonmetal at normal temperatures and pressure and is generally accepted to be part of the nonmetal group.
The halogens are nonmetals in group 7 of the periodic table. Atoms of these elements have the -1-oxidation state. The elements at the top of the group are gases, but they become liquids and solids moving down the group. The halogens are fluorine, chlorine, bromine, iodine, and astatine. The properties of tennessine are not well-known. Tennessine might be a halogen or it might be a metalloid.
The noble gases are relatively nonreactive gases found in group 8 (the last column) of the period table. The noble gases are helium, neon, argon, krypton, xenon, radon, and oganesson. It’s likely oganesson is not a gas at room temperature.
More Resources: What are the Nonmetals?
Properties of Nonmetals
Elements that tend to gain electrons to form anions during chemical reactions are called non-metals. These are electronegative elements with high ionization energies. They are non-lustrous, brittle, and poor conductors of heat and electricity (except graphite). Non-metals can be gases, liquids, or solids.
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). Only bromine exists as a liquid at room temperature.
- 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.
- Melting and Boiling Points: When a metal melts or boils, this is a change of physical state. Energy is transferred to a substance to melt or boil it. This energy is needed to overcome the forces of attraction between the metal ions and the delocalized electrons in the metal. The more energy needed, the higher the melting point or boiling point. As metals are giant lattice structures, the number of electrostatic forces to be broken is extremely large, and so metals have high melting and boiling points. This means that the melting point and boiling point of metals are more similar to those for ionic compounds than for covalent substances.
- Seven non-metals exist under standard conditions as diatomic molecules: H2(g)H2(g), N2(g)N2(g), O2(g)O2(g), F2(g)F2(g), Cl2(g)Cl2(g), Br2(l)Br2(l), I2(s)I2(s).
Chemical Properties of Nonmetals
Non-metals have a tendency to gain or share electrons with other atoms. They are electronegative in character. Nonmetals, when reacting with metals, tend to gain electrons (typically attaining noble gas electron configuration) and become anions:
Compounds composed entirely of nonmetals are covalent substances. They generally form acidic or neutral oxides with oxygen that dissolve in water to form acids:
CO2(g)+H2O(l)→H2CO3(aq)carbonic acidCO2(g)+H2O(l)→H2CO3(aq)carbonic acid
As you may know, carbonated water is slightly acidic (carbonic acid).
Nonmetal oxides can combine with bases to form salts.
Location of Nonmetals on the Periodic Table
Nonmetals are located on the far-right side of the periodic table, except hydrogen, which is located in the top left corner.
The 17 nonmetal elements are hydrogen, helium, carbon, nitrogen, oxygen, fluorine, neon, phosphorus, sulfur, chlorine, argon, selenium, bromine, krypton, iodine, xenon, and radon.
Uses of Nonmetals
Unlike metals, nonmetals do not have universal applications. But they do appear together in certain applications:
- Essential for life (carbon, hydrogen, nitrogen, oxygen, sulfur, chlorine, phosphorus)
- Fertilizers (hydrogen, nitrogen, phosphorus, sulfur, chlorine, selenium)
- Refrigerants and cryogenics (hydrogen, helium, nitrogen, oxygen, fluorine, neon)
- Industrial acids (carbon, nitrogen, fluorine, phosphorus, sulfur, chlorine)
- Lasers and lamps
- Medicine and pharmaceuticals
Nonmetals form many compounds. In fact, most compounds you encounter contain nonmetals. They occur in water, food, fabrics, plastics, and other everyday items.
Properties of Metals and Non-Metals- What’s the Difference?
|State at room temperature||Solid (except mercury, which is a liquid)||About half are solids, about half are gases, and one (bromine) is a liquid|
|Density||High (they feel heavy for their size)||Low (they feel light for their size)|
|Malleable or brittle||Malleable (they bend without breaking)||Brittle (they break or shatter when hammered)|
|Conduction of heat||Good||Poor (they are insulators)|
|Conduction of electricity||Good||Poor (they are insulators, apart from graphite)|
|Magnetic material||Only iron, cobalt, and nickel||None|
|Sound when hit||They make a ringing sound (they are sonorous)||They make a dull sound|
|Type of oxide||Basic or alkaline||Acidic|
Metalloid On The Periodic Table
Metalloid elements, also known as semimetals, are elements that have properties of both metals and nonmetals. The metalloid definition is considered to include between six to nine elements that occur along a slanted line between the metal and nonmetal elements of the periodic table.
The six elements that are unanimously considered to be metalloids are the following: Boron, Silicon, Germanium, Arsenic, Antimony, Tellurium.
Apart from these six elements, the definition of metalloid elements sometimes includes the elements bismuth, polonium, and astatine as well. This ambiguity is in large part due to a lack of specific properties that are considered characteristics of all metalloids.
Instead, the metalloid elements are simply characterized as having a mix of properties that are in between the properties of metals and nonmetals. Structurally, they form covalent bonded crystal structures, which is a characteristic found primarily in non-metals.
One well-known use of some metalloid elements is as a semiconductor found inside many of the electronic devices that are used in every household.
Properties of Metalloids
Metalloids have properties intermediate between metals and nonmetals. Metalloids are useful in the semiconductor industry. Metalloids are all solid at room temperature. They can form alloys with other metals.
Some metalloids, such as silicon and germanium, can act as electrical conductors under the right conditions, thus they are called semiconductors. Silicon for example appears lustrous but is not malleable nor ductile (it is brittle – a characteristic of some nonmetals).
It is a much poorer conductor of heat and electricity than metals. The physical properties of metalloids tend to be metallic, but their chemical properties tend to be non-metallic. The oxidation number of an element in this group can range from +5 to -2, depending on the group in which it is located.
Common Properties of Metalloids
In general, metalloids share the following common properties:
- The electronegativities of metalloids are between those of nonmetals and metals.
- Ionization energies of metalloids are also between those of nonmetals and metals.
- Semimetals/metalloids have some characteristics of nonmetals and some characteristics of metals.
- The reactivity of metalloids depends on the properties of the elements they are interacting with.
- Metalloids tend to be good semiconductors.
- Metalloids may have a metallic luster, but they also have tropes that can have a nonmetallic appearance.
- Metalloids are usually brittle, and they are also typically solid, only becoming non-solid under uncommon conditions.
- Metalloids typically behave as nonmetals in chemical reactions, and they can create alloys with metals.
Chemical properties of Metalloids
Chemical properties are those which defined how a substance interacts/reacts with other substances or changes from one substance to another substance. Chemical reactions are the only time that the chemical properties of an element can be quantified. Chemical reactions include things like rushing, burning, tarnishing, exploding, etc. The chemical properties of metalloids are as follows:
- Metalloids easily form gasses when they oxidize.
- Metalloids can be combined with metals to create alloys.
- Metalloids have different metallic and non-metallic allotropes.
- When metalloids melt some of them will contract.
- Metalloids can react with halogens to form compounds.
Location of Metalloids on the Periodic Table
As previously mentioned, metalloids are a group of elements that occur in a slanted line between the metals and nonmetals on the periodic table. This line of metalloid elements spans between Group 13 to Group 16, 17, or 18 (depending on how many elements are considered to be metalloids truly).
To the left of this line of metalloid elements are the elements classified as metals, and to its right are elements classified as non-metals. The one exception to this rule is the element hydrogen, which is classified as a nonmetal but occurs on the left side of the periodic table.
Periodic table of elements with the six metalloid elements (beginning with boron (B)) marked with a beige color. This group sometimes also includes the elements bismuth (Bi), polonium (Po), and astatine (At) from period 6 of the table.
More Resources: Where are Metalloids on the Periodic Table?
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 electronegativity and ionization energy values).
Within any group of elements (columns), the metallic character increases from top to bottom (the electronegativity and ionization energy values generally decrease as we move down a group). This general trend is not necessarily observed with the transition metals.