There are 118 known elements, of which 92 occur naturally, while the remaining ones have been synthesized. Based on their properties, which correspond to their spot on the periodic table, elements are further classified as metals, non-metals, and metalloids.
Based on chemical and physical properties, metals and non-metals can be differentiated. Metals are elements that can exhibit malleability, ductility, and sonorousness and are excellent heat and electrical conductors. Non-metal elements are neither malleable, ductile, nor sonorous and are weak heat and electricity conductors.
Metals
Except for hydrogen, elements that form positive ions by shedding electrons during chemical reactions are referred to as metals. Consequently, metals are electropositive elements with low ionization energies. They have a brilliant sheen, are rigid, capable of producing sounds, and are excellent thermal and electrical conductors. Except for mercury, metals are solid in normal conditions.
Properties Of Metals
Examples of metals are gold, silver, iron, aluminum, magnesium, etc. There are two types of properties possessed by metals: physical and chemical, which are discussed below:
Physical Properties Of Metals
Physical properties are metal are discussed here:
Physical State: Generally, metals are solids at room temperature. However, there are some exceptions, like mercury, which is liquid at room temperature, and gallium, which also changes its state to liquid during hot summers.
Malleability: Metals possess the ability to be beaten into thin sheets without any cleavage. This property allows metals to be shaped into the required design. Gold is one of the most malleable metals that can be hammered into thin sheets and used for jewelry and food.
Ductility: Metals can be drawn into thin wires without breaking them. This property is known as ductility. It allows metals to be shaped into thin wires. Copper is one example of a metal that can be drawn into thin wires and used inside wires and cables.
Hardness: Metals cannot be easily cut. Because they are soft and pierceable with a knife, sodium, and potassium are exceptions to this rule. Try cutting the gold or silver with your knife if you are rich.
Tensile-Strength: Metals have high tensile strength, with some exceptions. This property makes metal useful in alloys that are used for the construction of heavy structures.
Conductivity: Metals are good conductors because they have free electrons. Metals like copper and gold, known as good electrical conductors, are also good thermal conductors. There are some exceptions, as lead is the poorest conductor of heat.
Density: Metals are dense and incredibly weighty. Iridium and osmium have the greatest density, while lithium has the least.
Melting point and Boiling point: Metals have high melting and boiling points. This property is used to create alloys. For example, an alloy with a high percentage of tin or aluminum will melt at a much lower temperature than one with mostly iron and nickel.
Sonorous: Metal possesses a specific type of characteristics meaning it can create a sound when struck with a hard object. This property is known as sonorous property.
Chemical Properties Of Metals
Typically, the outer shell of metallic elements contains 1, 2, or 3 electrons. The greater the activity of a metal, the fewer valence electrons there are. By shedding electrons, they produce cations. In general, the vapor-state metal molecule is monatomic. In most cases, they form fundamental oxides. They are termed reducing agents because they ionize by giving up electrons. Some of the chemical properties of metals are discussed below:
Metals Reaction With Oxygen
Most metals react with oxygen to form metal oxide. Generally, metal oxides are basic in nature, but some metal oxides, such as aluminum oxide and zinc oxide, show both acidic and basic behavior. Such metal oxides, which react with both acids and bases to produce salt and water, are called amphoteric oxides.
Metal + Oxygen → Metal Oxide
Examples Of Metal and Oxygen Reactions:
At room temperature, Magnesium metal reacts with oxygen to form magnesium oxide.
2 Mg + O2 → 2 MgO
When sodium metal reacts with oxygen at room temperature, it generates sodium oxide.
4 Na + O2 → 2 Na2O
When potassium metal reacts with oxygen at room temperature, it generates potassium oxide.
4 K + O2 → 2 K2O
Sodium and potassium have a vigorous reaction with oxygen. When sodium and potassium are exposed to the air, they ignite.
Gold (Au) and silver (Ag) do not react with oxygen, even at elevated temperatures.
Metals Reaction With Water
When metals react with water, they produce metal oxide, hydroxide, and hydrogen. When metals react with water, they generate metal oxide and hydrogen gas. Metal oxides soluble in water form metal hydroxides by dissolving in water.
Metal + Water → Metal hydroxide + hydrogen
Examples Of Metal And Water Reactions:
When sodium metal reacts with water, it generates sodium hydroxide and hydrogen gas.
Na + H2O → NaOH + H2
When calcium reacts with water, it generate calcium hydroxide and hydrogen.
Ca + 2 H2O → Ca(OH)2 + H2
Due to a thin but resistant layer of aluminum oxide on its surface, aluminum metal does not react with water under typical conditions. The reaction between aluminum metal and steam produces aluminum oxide and hydrogen gas.
2 Al + 3 H2O → Al2O3 + 3 H2
Iron combines with moisture in the air (iron oxide) to create rust. The reaction between iron and steam produces iron oxide and hydrogen gas.
3 Fe + 4 H2O → Fe3O4 + 4 H2
When magnesium reacts with hot water, it forms magnesium oxide and hydrogen gas. Magnesium does not react with cold water.
Mg + H2O → MgO + H2
Metals like copper, nickel, and silver, among others, do not react with water or steam because they are the least reactive.
Metals Reactions With Acids
Metal reacts with dilute acids to form metal salts and hydrogen gas. However, not every metal reacts with diluted acids. The chemical reactivity of a metal determines how it reacts with moderate acids. Some metals react explosively or incredibly quickly, while others react slowly. Some metals respond to heat, while others do not.
Metal + Dilute Acid → Metal Salt + Hydrogen
Examples Of Metal And Acid Reactions:
When magnesium metal reacts with hydrochloric acid, magnesium chloride, and hydrogen gas are generated.
Mg + 2 HCl → MgCl2 + H2
When iron reacts with hydrochloric acid, magnesium chloride and hydrogen gas are generated.
Fe + H2SO4 → FeSO4 + H2
When zinc metal reacts with dilute sulfuric acid, it generates zinc sulfate and hydrogen gas
Zn + H2SO4 → ZnSO4 + H2
Metals Reactions With Bases
Metals react with basic salt to generate hydrogen gas.
Metal + Base → Metal salt + hydrogen
Examples Of Metal Reaction With Base
When aluminum reacts with sodium hydroxide, it forms sodium aluminate and hydrogen gas.
Al + NaOH → NaAlO2 + H2
Metals Reaction With Other Metal Salts
When metals interact with a solution of another metal chloride, a displacement reaction takes place. In this reaction, the more reactive element displaces the less reactive element from its salt.
Metal X + Salt of metal Y → Salt of Metal X + Metal Y
Example Of Metal Reaction With Other Metal Salts
Iron displaces copper from the copper (II) sulfate solution to form ferrous sulfate.
Fe + CuSO4 → FeSO4 + Cu
Zinc displaces copper from the copper (II) sulfate solution to form zinc sulfate.
Zn + CuSO4 → ZnSO4 + Cu
Uses Of Metals
Typically, metals are robust, long-lasting, and resistant to everyday wear and tear. As such, they have been utilized for numerous purposes since antiquity. And even today, after technological advancements and different other factors, the applications of metals have expanded significantly. Metals play an important role in the economy. Consider some essential and widespread metal applications.
Metals have been utilized for centuries and in nearly every aspect of our lives today. Some Some of the common uses of metals are:
Electronics: Electronics such as refrigerators, televisions, air conditioners, telephones, and every other electric device rely predominantly on electrical power for operation. From electrical wires to parts of electronics, metal is widely used. For example, iron, copper, silver, and gold
Machinery and Automobiles: Railways, cars, rockets, satellites, and aircraft are included within the scope of machinery and automobiles. Given their capacity to withstand tremendous pressure and high temperatures while performing their duties, these devices are primarily made of metals and their alloys. Aluminum, iron, and platinum are some examples.
Construction: Several engineering marvels, including the Burj Khalifa and the Eiffel Tower, have utilized these metals. Due to their load-bearing capacity and overall strength, steel, iron, and alloys are the preferred construction materials. Fencing, columns, reinforced concrete roofs, and foundations are popular applications.
Jewelry: Physical properties of metals like ductility, malleability, durability, and luster make them valuable. Platinum, gold, copper, and silver are some of the most sought-after jewelry materials in the world.
For more use of the metals, you can look at the periodic table sections where the use of every metal is discussed.
Non-Metals
Non-metals are the elements that form negative ions by gaining electrons. Nonmetals are electronegative. Hydrogen is the only non-metal that loses electrons. It forms an acid if combined with oxygen and hydrogen. In comparison to metals, non-metals display more variety in color and state. Hydrogen, chlorine, fluorine, carbon, nitrogen, phosphorus, and selenium are some examples of non-metals.
Properties Of Non-Metals
Examples of non metals are hydrogen, chlorine, fluorine, carbon, etc. There are two types of properties possessed by metals: physical and chemical, which are discussed below:
Physical Properties Of Non-Metals
Physical State: At ambient temperature, non-metals can exist in solid, liquid, or gaseous states. Sulfur and carbon, for instance, are solids at room temperature; bromine is a liquid; and nitrogen and oxygen are gaseous non-metals.
Non-metals are brittle: Non-metallic substances cannot be pounded or hammered into thin sheets without shattering. When hammered or stretched, non-metals splinter into fragments. As granules, sulfur, and phosphorus cannot be formed into sheets. Non-metallic substances have the characteristic property of fragility.
Non-metals are rigid: Nonmetallic substances cannot be melted and drawn into threads. Non-metallic substances lack unbound electrons. Therefore, the bonds between atoms in the elements are weak and easily break when stretched. Non-ductility is a consequence of either non-malleability or brittleness.
Non-Metals are insulator: The bonds produced in non-metals are weak because there are no free electrons to share. Other than graphite, an allotrope of carbon, none of the non-metals are heat or electricity conductors. Graphite can conduct electricity due to its unique crystalline structure. Non-metals can be used as insulator.
Density: When compared to metals, the density of non-metals is lower. This indicates that in non-metals, the atoms are not tightly bound. Non-metals have a minimal crystalline volume.
Hardness: Due to their lack of ductility and malleability, non-metals lack strength. Their bonds are readily broken because they do not share electrons.
Melting point and Boiling point: Generally, the melting and boiling points of nonmetals are low. There are some exceptions. Graphite and diamonds have high melting points.
Chemical Properties Of Nonmetals
Non-metallic elements usually have 5, 6, or 7 electrons in their outer shell. They form anions (negative ions) by gaining electrons to complete their octet. Their molecules are mostly polyatomic in the gaseous state and can form acidic oxides. Nonmetals, which ionize by gaining electrons, are known as oxidizing agents.
Nonmetals Reaction With Oxygen
Nonmetallic substances react with oxygen to form nonmetallic oxides. Non-metal oxides are acidic or neutral. Non-metal oxide bonds are covalent bonds. Non-metal atoms and oxygen atoms share electrons to form non-metal oxide. All non-metals ignite in the air or oxygen to produce non-metal oxides.
Examples Of Nonmetals Reaction With Water
When sulfur (S) reacts with oxygen (O2), it generates sulfur dioxide (SO2).
S + O2 → SO2
Sulfur dioxide and water react, forming sulfurous acid.
SO2 + H2O → H2SO3
Carbon and oxygen react to create carbon dioxide.
C + O2 → CO2
Similar to sulfur dioxide, when carbon dioxide is dissolved in water, it forms carbonic acid.
CO2 + H2O → H2CO3
When phosphorus reacts with oxygen, it creates phosphorus pentoxide.
(c) P4 + 5O2 → 2 P2O5
When phosphorus pentoxide is further dissolved in water it generates, phosphoric acid.
P2O5 + 3 H2O → 2 H3PO4
Reactions Of Non metals With Acids
The majority of non-metallic substances do not react with dilute acids. They cannot replace the hydrogen in the acids and form a salt. Carbon, sulfur, and phosphorus do not react with HCl or H2SO4 to produce hydrogen. The reason for this was explained previously. To liberate H+ from the acid, the nonmetal must donate an extra electron. Non-metals are intrinsic electron acceptors. Therefore, they cannot displace H+ from the acid to form a salt and liberate hydrogen gas.
Reactions Of Nonmetals With Hydrogen
Hydrogen reacts with non-metals to form hydrides.Hydrogen, being a non-metal, forms covalent bonds and, consequently, hydrides. These compounds are covalent, unlike metal hydrides.
Examples of Nonmetals Reaction With Hydrogen
When sulfur (S) reacts with hydrogen (H2), it forms hydrogen sulfide (H2S).
H2 + S → H2S
Oxygen reacts with hydrogen to form a neutral non-metal hydride (water).
2 H2 + O2 → 2 H2O
When nitrogen (N2) reacts to hydrogen (H2), it produces ammonia (NH3).
N2 + 3 H2 → 2 NH3
Reactions Of Non metals With Halogens
Halides are formed when non-metals form covalent bonds with halogens. There are a lot of compounds with the same halogen because different non-metals have different electronegativity. These halides are also hydrolyzed. Non-metallic substances react with chlorine (Cl) to produce chlorides. In solution, these covalent compounds do not behave as electrolytes.
Examples Of Nonmetals Reaction With Halogen (chlorine)
When phosphorus reacts with chlorine (Cl), it forms covalent chlorides, phosphorus trichloride, and phosphorus pentachlorides. Reactions are given below in their respective order:
Phosphorus trichloride
P4 + 6 Cl2 → 4 PCl3
Phosphorus pentachloride
P4 + 10 Cl2 → 4 PCl5
Reactions Of Nonmetals With Salt Solution
When a non-metal is added to a salt solution, its reactivity determines the outcome. More reactive nonmetals displace the less reactive nonmetals in the salt solution. For instance, chlorine, being more reactive, it will displace the bromine from sodium bromide to form sodium chloride.
Examples Of Nonmetals Reaction With Salt Solution
Sodium chloride (NaCl) and bromine (Br2) are produced when chlorine (Cl) is passed through a solution of sodium bromide (NaBr).
2 NaBr + Cl2 → 2 NaCl + Br2
Reactions Of Non metals As Oxidizing Agents
Besides carbon, every non-metal accepts electrons. Consequently, they are oxidizing agents because they remove electrons from the surrounding elements. Chlorine is an oxidizing agent because its outer orbit acquires an electron. Even though chlorine is an oxidizing agent, it is becoming a chlorine ion, which is an intriguing observation. Carbon is a reducing agent when it gives up its electrons during a chemical reaction.
Examples Of Nonmetal Reactions as Oxidizing Agent
Metals act as oxidizing agents and non-metals as reducing agents to form ionic compounds.
Zinc sulfide
Zn + S → Zn2 + S2–
Sodium chloride
2 Na + Cl2 → 2 Na + Cl–
Reactions Of Non metals With Water
Water does not react with nonmetals. This is due to the electronic configuration of non-metals. Electronegative non-metals cannot break the bond between hydrogen and oxygen in water. Whether the water is frigid, hot, or steaming, none of the non-metallic substances react to it. Non-metals cannot donate electrons to reduce hydrogen. Non-metallic substances never react with water because they always form electronegative compounds.
Uses Of Nonmetals
Nonmetallic substances exist in all three phases of matter. They have a range of practical applications, from propelling the global economy to providing essential materials for daily operations. Non-metallic substances play a significant role by supplying essentials for industrial functions.
Some of the applications of nonmetals are discussed here:
Essential For all Living things: Our very existence depends on the oxygen. In the atmosphere, oxygen is an element essential to existence. For respiration, oxygen is necessary for all organisms.
Used In Fertilizers: Nonmetals are used in the production of fertilizers. Nitrogen, sulfur, and phosphorus are essential for the growth of plants. They provide the nutrients required for plants and crops.
Purification: Non-metals like oxygen and chlorine are purifiers. Chlorine is used in water purification. Oxygen is also helpful in water purification as it is used in ozone gas. This helps reduce the bacteria level in the water.
Used in Different Products: Bromine is utilized in batteries, pigments, medications, and photography. In the form of tincture iodine, iodine is used as an antiseptic. For the cutting and welding procedures, oxygen is utilized. Silicon is present in numerous products, ranging from glassware and computer processors to rubber soles.
For more use of the non metals, you can look at the periodic table sections where the use of every metal is discussed.
Difference Between Metals And Non-metals
| Properties | Metals | Non-Metals |
|---|---|---|
| Physical State | Solid (except mercury and gallium at hot days) | All three states: Solid, Liquid,and Gaseous |
| Luster | Shiny reflective appearance | Dull and Non-reflective |
| Hardness | Hard, Durable, Malleable, and Ductile | Soft and Brittle |
| Heat Resistance | High Melting and Boiling Points | Low Melting and Boiling points |
| Density | High Density | Low Density |
| Conductivity | High thermal and electrical conductivity | Low thermal and electrical conductivity |
| Ionization | Tends to lose electrons and form positive ions | Tends to gains electrons and form negative ions |
References
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