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  118 elements are currently known. There are more than 90 metals, 22 non-metals, and some metalloids.

metals and non-metals class 10 notes

️ Metal:-

Materials that are hard, shiny, malleable, ductile, acoustic, and good conductors of heat and electricity are called metals.

Such as: - sodium (Na), potassium (K), magnesium (Mg), iron (Fc), aluminum (AI), calcium (Ca), barium (Ba) are metals.

️ Uses of metals:-

Metals are used in making buildings, bridges, railway tracks, in the manufacture of airplanes, ships, vehicles, utensils, ornaments, machine parts, etc.

️ Non-metals:-

The substances which are soft, turbid, brittle, poor conductors of heat and electricity, and which are not acoustic are called non-metals.

Such as - Oxygen (O), Hydrogen (H), Nitrogen (N), Sulfur (S), Phosphorus (P), Fluorine (F), Chlorine (CI), Bromine (Br), and Iodine (I), are non-metals.

️ Uses of non-metals:-

Oxygen is essential for our life, which living beings take in during respiration.

• Nitrogen is used in fertilizers for plant growth.

• Chlorine is used in the water purification process.

• Iodine solution is applied to wounds as an antibiotic.

Physical condition: Metals are generally solid and hard. The hardness of each metal is different. Metals have higher melting points.

Shine: The surface of the metal in its pure form is shiny. This property of a metal is called metallic luster.

Malleability:- Thin sheets can be made by beating metals. This property is called malleability. Gold and silver are the most malleable metals.

Tensile: The ability of a metal to be stretched in the form of a thin wire is called tensile. Gold is the most ductile metal, a wire 2 km long can be made from one gram of gold.

Conductivity: Metals are good conductors of heat and electricity. Silver and copper are good conductors.

Acoustic:- Generally metals produce a special sound when they hit a hard surface, hence they are called acoustic.

physical properties of metals and non-metals class 10:

Physical State: Non-metals are generally either solids or gases.

 Shine: Non-metals do not have luster.

Malleability: Non-metals are not malleable. Non-metals are brittle, so they break when they are beaten.

Tensile: Non-metals are not ductile.

Conductivity: Non-metals are poor conductors of electricity and heat.

chemical properties of metals and non-metals class 10:-

1. Combustion of metals in air:-

The chemical process in which a substance reacts with oxygen to give heat is called combustion.

Generally, the combustion of metals in air is accompanied by a bright flame and almost all metals combine with oxygen to form oxides of the corresponding metal.

metal + oxygen → metal oxide

For example, when copper is heated in the presence of air, it combines with oxygen to form black-colored copper (II) oxide.

(Copper) 2Cu + 0₂ → 2Cuo [Copper (II) Oxide]

Similarly, aluminum gives aluminum oxide.

(Aluminum) 4Al + 3O₂ → 2Al₂O₃ [ aluminum oxide ]

Properties of metal oxides:-

Generally, the nature of metal oxides is basic. The basic nature of oxides means that they react with acids to give salt and water.

But some metal oxides like aluminum oxide, and zinc oxide show both acidic and basic behavior.

Aluminum oxide reacts with acid and base in the following way

Al₂O₃ + 6HCl → 2AlCl₃ , + 3H₂O

Al₂O₃ + 2NaOH → 2NaAlO₂ + H₂O

sodium aluminate

Most of the metal oxides are insoluble in water but some of them dissolve in water to give alkali.

Sodium oxide and potassium oxide dissolve in water to give alkali in the following way.

Na₂O(s) + H₂O(I) → 2NaOH (aq)

 K₂O(s) + H₂O(l) → 2KOH (aq)

️ Amphoteric Oxide:-

Such metal oxides which react with both acid and base to give salt and water are called amphoteric oxides.

Reactivity of metals with oxygen:-

Metals exhibit different types of reactivity with oxygen:-

• Some metals like potassium and sodium react so fast that they catch fire when kept in the open.

• Silver and gold do not react with oxygen even at very high temperatures.
  

• At normal temperatures, metals like magnesium, aluminum, zinc, lead, etc. have a thin layer of oxide on their surface. This layer of oxide protects the metals from re-oxidation (action with oxygen).

• Iron does not burn when heated, but when the iron powder is put in the flame of a burner, it starts burning rapidly.

2. Reaction of metals with water:-

Metals react with water to produce hydrogen gas and metal oxides. Some metal oxides are soluble in water, which dissolves in water to give metal hydroxides. But not all metals react with water.

Metal + Water → Metal Oxide + Hydrogen

Metal Oxide + Water → Metal Hydroxide

Example:-

️ a. Metals like potassium and sodium react rapidly with cold water. The reaction of sodium and potassium is fast and exothermic, so the hydrogen emitted from it immediately ignites.

2K(s) + 2H₂O(l) → 2KOH(aq) + H₂(g) + thermal energy

2Na(s) + 2H₂O(l) → 2NaOH(aq) + H₂(g) + thermal energy

️ B. Reaction of calcium with water is a little slow. The heat emitted here is not enough for the hydrogen to ignite.

Ca(s) + 2H₂0(l) → Ca(OH)₂(aq) + H₂(g)

The bubbles of hydrogen gas produced in the above reaction stick to the surface of calcium metal. So calcium starts floating.

️ C. Magnesium does not react with cold water, but reacts with hot water to produce magnesium hydroxide and hydrogen gas. The hydrogen gas bubbles stick to the surface of the magnesium metal. So it also starts swimming.

️ D. Metals like aluminum, iron, and zinc neither react with cold water nor with hot water. But on reacting with steam, these metals give oxides and hydrogen.

2Al(s) + 3H₂0(g) → Al₂0₃(s) + 3H₂(g)

3Fe(s) + 4H₂O(g) → Fe₃O₄(s) + 4H₂(g)

️ E. Metals like lead, copper, silver, and gold do not react with water at all.

3. Reaction of metals with acids class 10:-

Metals react with acids to give corresponding salts and hydrogen gas.

Metal + Dilute Acid → Salt + Hydrogen

Sodium and potassium metals react very quickly with acids.

The rate of reaction of different metals with dilute acids like (aq.HCl) is given below. Mg > Al > Zn > Fe . Copper does not react with dilute HCl.

4. Reactions of metals with solutions of metal salts:-

The more reactive metal displaces the less reactive metal from the solution or molten state of its compound. This is called displacement reaction.

If metal (A) displaces metal (B) from its solution, then it is more reactive than metal (B).

Salt solution of metal ( A ) + ( B ) → salt solution of ( A ) + metal ( B )

️ Activity Category:-

The activity series is the list in which the reactivity of metals is arranged in descending order.

Activity Category

The reaction of metals with non-metals:-

The reactivity of elements can be understood as the tendency to complete the valence shell. ,

• Metal atoms lose electrons from their valence shells and form cations.

• Atoms of nonmetals form anions by accepting electrons in the valence shell.

• Oppositely charged ions attract each other and bind with strong electrostatic force to form ionic compounds.

️ properties of ionic compounds class 10:-

Physical nature:- Ionic compounds are solid and hard due to the strong attraction force between positive and negative ions. These compounds are generally brittle and break into pieces when pressed.

Melting point and boiling point:- Ionic compounds have a very high melting points and boiling points because a sufficient amount of energy is required to break the strong inter-ionic attraction.

Solubility:- Electrovalent compounds are generally soluble in water and insoluble in solvents like kerosene, petrol, etc.

Electrical conductivity:- Ionic compounds in a solid state do not conduct electricity, because ions movement is not possible in a solid state due to rigid structure. But in a molten or aqueous state, ions move freely and conduct electricity.

️ Receipt of metals:-

The Earth's crust is the main source of metals.

Minerals: - The elements or compounds that occur naturally in the earth's crust are called minerals.

Ore:- In some places minerals contain a large amount of a particular metal, which is beneficial to extract. These minerals are called ores.

️ Extraction of metals:-

On the basis of reactivity, we can divide metals into the following three classes:-

low reactive metals

medium reactive metals

Highly reactive metals.

Different techniques are used to obtain the metals that fall in each class.

Metals that fall in the reactivity series are the least reactive. They are found in the free state. For example, gold (gold), silver (silver), platinum, and copper (copper) are found in the free state. Copper and silver are also found in the combined state as ores of their sulfides or oxides.

The metals at the top of the reactivity series (K, Na, Ca, Mg, and Al) are so reactive that they are never found as independent elements. The extraction of pure metal from the ore takes place in the following steps.

️ 1. Enrichment of ores:-

Mineral ores from the earth contain many impurities like clay, sand, etc., which are called gangue. The processes used to remove gangue from ores are based on the physical or chemical properties of the ore and gangue. Various techniques are used for this separation.

2. Extraction of metals falling below the activity series:-

The metal can be obtained only by heating the oxides of these metals.

For example:- Cinnabar (HgS) is an ore of mercury. On heating in air, it first converts to mercuric oxide (Hg0) and on further heating, the mercuric oxide is reduced to mercury (mercury).

2HgS(s) + 3O₂(g) [Heating →] 2HgO(s) + 2SO₂(g)

2HgO(s) [ Heating → ] 2Hg(l) + O₂(g)

️ 3. Extraction of metals located in the middle of the activity series:-

In nature, it is often found in the form of sulfide or carbonate. It is easier to obtain metals from their oxides than from sulfides or carbonates, so carbonates and sulfides are first converted to oxides.

a . Roasting: When sulphide ore is heated in the presence of air at a high temperature, it gets converted into oxide. This process is called roasting.

Heating Roasting of Zinc Sulphide Ore :- 2ZnS(s) + 3O₂(g) [Heating → ] 2ZnO(s) + 2SO₂(g)

b. Calcination: By heating the carbonate ore in confined air at high temperatures, it gets converted into oxide. This process is called calcination.

Heating Calcination of Carbonate Ore of Zinc :- ZnCO₃(s) [Heating → ] ZnO(s) + CO₂(g)

c. Reduction:- Metals are obtained from metal oxides obtained by roasting or calcination using a suitable reducing agent such as carbon. For example, when zinc oxide is heated with carbon, it is reduced to zinc metal.

 ZnO(s) + C(s) [ Heating → ] Zn(s) + CO(g)

Fe₂O₃(s) + 2Al(s) → 2Fe(l) + Al₂O₃(s) + heat

️ 4. Extraction of metals at the top of the activity series:-

These metals are obtained by electrolytic reduction.

For example: - Sodium, magnesium, and calcium are obtained by electrolysis of their molten chlorides. The metals are deposited at the cathode (negatively charged electrode) and chlorine is liberated at the anode (positively charged electrode).

The reactions are as follows:-

Na⁺ + e⁻ → Na at the cathode

2Cl⁻ → Cl₂ + 2e⁻ at the anode

Similarly, aluminum is obtained by electrolytic reduction of aluminum oxide.

️ 5. refining of metals class 10:-

The metals obtained by various reduction processes are not completely pure. They contain impurities that can be removed only to obtain pure metal. The most commonly used method for removing impurities from metals is electrolytic refining.

️ Electrolytic Refining:-

The refining of many metals like copper, zinc, tin nickel, silver, gold, etc. is done by electrolysis.

In this process, the impure metal is made anode and a thin layer of pure metal is made as the cathode.

The salt solution of the metal is used as an electrolyte.

After passing electricity, the impure metal in the anode dissolves in the electrolyte. And the same amount of pure copper is deposited at the cathode by the electrolyte.

Insoluble impurities are deposited at the bottom of the anode, which is called anode mud.

️ Corrosion:-

When metal starts to decay after coming in contact with the substances present in the environment (mainly oxygen, acid, humidity, etc.), it is called corrosion.

Corrosion of Silver: - Silver articles turn black when left in the open air for a few days. This is due to the reaction of silver with the sulfur present in the air to form a layer of silver sulfide (AgS).

Corrosion of copper:- Copper gradually loses its brownish luster due to the reaction with the moist CO₂ present in the air and a green layer of alkaline copper carbonate is plated on it.

Corrosion of iron: - When exposed to moist air for a long time, iron gets coated with a brownish substance called rust (Fe₂O₃. nH₂O).

️ Protection against corrosion:-

Corrosion can be prevented or slowed by painting, oiling, applying grease, lacquering, chromium coating, anodizing or alloying metals.

️ Success:-

To protect the iron and steel from rust, it is called a thin layer of zinc on them.

️ Alloy:-

The homogeneous mixture of two or more metals (sometimes non-metals are also present) is called alloy/alloy.

To prepare it, first, the parent metal is brought to the molten state, and after that other elements are dissolved in it in a certain proportion. It is then cooled at room temperature.

If any one metal is mercury, then its alloy is called amalgam. The electrical conductivity and melting point of its alloy are lower than that of pure metals.

For example:-

• Brass alloys of copper and zinc (Cu and Zn) and bronze of copper and tin (Cu and Sn) are poor conductors of electricity, but copper is used in making electrical circuits.

• Solder, it is an alloy of lead and tin (Pb and Sn) which has a very low melting point and is used for welding electrical wires together.

difference between metals and non-metals

metals	non-metals
Except mercury, all are in solid form at room temperature.	Broadly speaking, bromine is a liquid nonmetal in all three states.
Tensile and malleable.	Non-metals are not ductile and malleable.
Has acoustic and luminance properties.	Non-metals are not acoustic and have no luster.
Generally high density, but sodium and potassium have low densities.	The density of non-metals is relatively low.
Metal oxides are alkaline or hot-stressed.	Nonmetal oxides are acidic in nature.
Metals displace hydrogen from dilute acids to form hydrogen gas.	Nonmetal oxides do not displace hydrogen from dilute acids.
Metal oxides are ionic.	Nonmetal oxides are covalent.