Notes On Metals and Non-metals - CBSE Class 10 Science
Metals: In general metals can be defined as the elements which have a tendency to lose electrons and form positively charged ions or cations.  Example: sodium has an electronic configuration of 2,8,1. During a chemical reaction, sodium can lose an electron to a non-metal like chlorine to form a sodium ion that has an electronic configuration of 2,8. Physical properties of metals: Physical state: All metals are solids at room temperature. Example: Iron and copper. The one exception is mercury, which is a liquid. Lustrous nature: All metals are lustrous. Metal surfaces shine when they are freshly cut.  Example: Gold and silver are popularly used for making jewellery because of their lustrous nature. Density: Metals have high densities and, therefore, tend to sink in water.  Example: Tin and lead sink in water.  Exceptions to this rule are lithium, sodium and potassium. The density of these elements is lower than that of water and hence they do not sink. Malleability: Metals are highly malleable, and can be beaten into thin sheets.  Example: Aluminium and zinc can be rolled into thin sheets. This property makes them suitable for use in various industries like construction and manufacturing. Ductility: Metals are highly ductile and can be drawn into wires.  Example: Copper and silver can be drawn into thin wires. Conductivity: Metals are good conductors of heat and electricity. Copper wires are commonly used in electric cables because of this property. Melting point: Metals have high melting points.  Example: Tungsten has a high melting point, due to which it is used in bulb filaments.  Mercury is an exception to this property, since it has a low melting point. Chemical properties of Metals: Metals react with non-metals to form ionic compounds.  Example: Sodium reacts with chlorine to form sodium chloride.             2Na + Cl2  → 2NaCl Reaction of metals with oxygen: Most of the metals combine with Oxygen to form basic metal oxides.  Example: When magnesium burns in oxygen it forms magnesium oxide.              2Mg + O2 → 2MgO Metal oxides of alkali metals soluble in water to form hydroxide solutions, called alkalies.  Example: Sodiumoxide soluble in water to form sodium hydroxide.              2Na2O + H2O →2 NaOH Reaction of metals with water: Sodium, potassium reacts vigorously even with cold water.              2Na + 2H2O → 2NaOH + H2              2K + 2H2O → 2KOH + H2 Calcium reacts slowly with cold water. And can react vigorously with hot water.              Ca + 2H2O → Ca(OH)2 + H2 Magnesium does not reacts with cold water. It reacts very slowly with hot water but reacts vigorously with steam.              Mg + 2H2O → Mg(OH)2 + H2 Iron and zinc do not react either with cold or hot water but react with steam.              Zn + H2O → ZnO + H2              Fe + H2O → FeO + Fe2O3 + H2 Aluminum do not reacts either with cold water, hot water and even steam because of its protective oxide layer. Metals like Lead, Copper, Gold and Silver do not show any reaction with water. Non-metals: Non-metals are elements that have a tendency to accept electrons to form negatively charged ions or anions.  Example: Chlorine has an electronic configuration of 2,8,7. During a chemical reaction, chlorine can accept an electron from a metal like sodium to form a chloride ion. A chloride ion has an electronic configuration of 2,8,8. Physical properties of non-metals: Physical state: Non-metals exist as solids, liquids and gases. Example: Silicon and carbon are solids; bromine is a liquid; chlorine, fluorine and oxygen are gases. Lustrous nature: Non-metals are non-lustrous and have a dull appearance in nature. Density: Most of the non-metals have very low density.  Example: Oxygen and nitrogen are lighter than air.  Exception is diamond, a form of carbon. Diamond is one of the strongest known substances. Non-metals are not malleable. Non-metals are bad conductors of heat and electricity.  Exception is graphite, a form of carbon which is a good conductor of electricity. Non-metals have low melting and boiling points.  Example: Sulphur and Phosphorus have low melting and boiling points. Chemical properties of non-metals: Formation of covalent compounds: Reaction between non-metals produces covalent compounds. Example: Hydrogen and chlorine reacts with each other form hydrogen chloride                 H2 + Cl2 → 2HCl Reaction of non-metals with oxygen: Non-metals reacts with oxygen to form oxides which are either acidic or neutral in nature. Example: Sulphur reacts with oxygen to form sulphur dioxide which is acidic in nature      S + O2 → SO2 Nitrogen reacts with limited supply oxygen to form nitric oxide which is a neutral oxide in nature.     N2 + O2 → 2NO Non-metal oxides dissolves in water to form acidic solutions. Example: Sulphur dioxide dissolves in water to form sulphurous acid.      SO2 + H2O → H2SO3 Non-metals are good oxidizing agents. Example: Sulphur in hydrogen sulphide undergoes oxidation when hydrogen sulphide reacts with chlorine.       H2S + Cl2 → 2HCl + S Metals and non-metals are separated through electrolysis

#### Summary

Metals: In general metals can be defined as the elements which have a tendency to lose electrons and form positively charged ions or cations.  Example: sodium has an electronic configuration of 2,8,1. During a chemical reaction, sodium can lose an electron to a non-metal like chlorine to form a sodium ion that has an electronic configuration of 2,8. Physical properties of metals: Physical state: All metals are solids at room temperature. Example: Iron and copper. The one exception is mercury, which is a liquid. Lustrous nature: All metals are lustrous. Metal surfaces shine when they are freshly cut.  Example: Gold and silver are popularly used for making jewellery because of their lustrous nature. Density: Metals have high densities and, therefore, tend to sink in water.  Example: Tin and lead sink in water.  Exceptions to this rule are lithium, sodium and potassium. The density of these elements is lower than that of water and hence they do not sink. Malleability: Metals are highly malleable, and can be beaten into thin sheets.  Example: Aluminium and zinc can be rolled into thin sheets. This property makes them suitable for use in various industries like construction and manufacturing. Ductility: Metals are highly ductile and can be drawn into wires.  Example: Copper and silver can be drawn into thin wires. Conductivity: Metals are good conductors of heat and electricity. Copper wires are commonly used in electric cables because of this property. Melting point: Metals have high melting points.  Example: Tungsten has a high melting point, due to which it is used in bulb filaments.  Mercury is an exception to this property, since it has a low melting point. Chemical properties of Metals: Metals react with non-metals to form ionic compounds.  Example: Sodium reacts with chlorine to form sodium chloride.             2Na + Cl2  → 2NaCl Reaction of metals with oxygen: Most of the metals combine with Oxygen to form basic metal oxides.  Example: When magnesium burns in oxygen it forms magnesium oxide.              2Mg + O2 → 2MgO Metal oxides of alkali metals soluble in water to form hydroxide solutions, called alkalies.  Example: Sodiumoxide soluble in water to form sodium hydroxide.              2Na2O + H2O →2 NaOH Reaction of metals with water: Sodium, potassium reacts vigorously even with cold water.              2Na + 2H2O → 2NaOH + H2              2K + 2H2O → 2KOH + H2 Calcium reacts slowly with cold water. And can react vigorously with hot water.              Ca + 2H2O → Ca(OH)2 + H2 Magnesium does not reacts with cold water. It reacts very slowly with hot water but reacts vigorously with steam.              Mg + 2H2O → Mg(OH)2 + H2 Iron and zinc do not react either with cold or hot water but react with steam.              Zn + H2O → ZnO + H2              Fe + H2O → FeO + Fe2O3 + H2 Aluminum do not reacts either with cold water, hot water and even steam because of its protective oxide layer. Metals like Lead, Copper, Gold and Silver do not show any reaction with water. Non-metals: Non-metals are elements that have a tendency to accept electrons to form negatively charged ions or anions.  Example: Chlorine has an electronic configuration of 2,8,7. During a chemical reaction, chlorine can accept an electron from a metal like sodium to form a chloride ion. A chloride ion has an electronic configuration of 2,8,8. Physical properties of non-metals: Physical state: Non-metals exist as solids, liquids and gases. Example: Silicon and carbon are solids; bromine is a liquid; chlorine, fluorine and oxygen are gases. Lustrous nature: Non-metals are non-lustrous and have a dull appearance in nature. Density: Most of the non-metals have very low density.  Example: Oxygen and nitrogen are lighter than air.  Exception is diamond, a form of carbon. Diamond is one of the strongest known substances. Non-metals are not malleable. Non-metals are bad conductors of heat and electricity.  Exception is graphite, a form of carbon which is a good conductor of electricity. Non-metals have low melting and boiling points.  Example: Sulphur and Phosphorus have low melting and boiling points. Chemical properties of non-metals: Formation of covalent compounds: Reaction between non-metals produces covalent compounds. Example: Hydrogen and chlorine reacts with each other form hydrogen chloride                 H2 + Cl2 → 2HCl Reaction of non-metals with oxygen: Non-metals reacts with oxygen to form oxides which are either acidic or neutral in nature. Example: Sulphur reacts with oxygen to form sulphur dioxide which is acidic in nature      S + O2 → SO2 Nitrogen reacts with limited supply oxygen to form nitric oxide which is a neutral oxide in nature.     N2 + O2 → 2NO Non-metal oxides dissolves in water to form acidic solutions. Example: Sulphur dioxide dissolves in water to form sulphurous acid.      SO2 + H2O → H2SO3 Non-metals are good oxidizing agents. Example: Sulphur in hydrogen sulphide undergoes oxidation when hydrogen sulphide reacts with chlorine.       H2S + Cl2 → 2HCl + S Metals and non-metals are separated through electrolysis

#### Activities

Activity 1 Learnthings.co has created an interactive video on “Reactivity of Metals and Reactivity series”. This video help to students to know how an experiment on reactivity can help to understand the reactive differences between metals. Student can understand how different metals can react with water and different acids. Go To Activity Activity 2 Education.vic has created a wonderful activity on “Non – metals”. This activity explains the properties of non -metals. Students will also understand how properties of elements are useful to classify them as non – metals. At the end of the video students can also test their knowledge. Go To Activity Activity 3 Hkedcity.net has created a wonderful activity on “Reactivity of Metals”. Through this activity students will learn the reactions of different metals with air, water and dilute acids. Students will also learn more about the natural source, production and applications of metals. Go To Activity

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