Metals & Non-Metals

Instructor  Dona Choudhury
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Periodic Table

Metals

  • Metals are substances which are electropositive in nature i.e., they have a tendency to lose electrons to complete their octet.
  • Examples:
  1. Sodium (Na) = 2,8,1
    Na –> Na+ + e
  2. Magnesium (Mg) = 2,8,2
    Mg –> Mg+2 + 2e

Non – Metals

  • Non-metals are substances which are electronegative in nature i.e., they have a tendency to accept electrons.
  • Example:
  1. 17Cl = 2,8,7
    Cl + e- –> Cl (2,8,8)
  2. 8O = 2,6
    O + 2e –> O2- (2,8)

Physical Properties

METALSNON-METALS
Metals are generally solid. Examples-  Iron, Gold and so on. Exception- Mercury, GalliumNonmetals exist in all three states of matter.
Solid- Carbon, Phosphorous, Iodine
Liquid- Bromine
Gases- Chlorine, oxygen, nitrogen and so on.

Metals

Non – Metals

METALSNON-METALS
Metals have lustre ( Ability to shine and reflect light surface) and can be polished. Except: Lead ( Have dull appearance)Nonmetals are dull. Except: Iodine, Diamond and graphite.
METALSNON-METALS
Metals are generally hard  Except: Mercury (Liquid), Gallium (Liquid in room temperature), Sodium, and Potassium are soft metalsNonmetals are generally soft. Except: Diamond is one of the hardest known substance.
METALSNON-METALS
Metals generally have a high melting point and boiling point. Except: MercuryNonmetals generally have low melting point and boiling point Except: Silicon, Boron ( Metalloids), Carbon ( Diamond).
METALSNON-METALS
Metals have high density.     
Except: Sodium and Potassium can be cut with knife.
Nonmetals have low density. Except: Diamond
METALSNON-METALS
Ductility: The property which allows the metals to convert them into thin wires. Eg- The most ductile metal is gold. One gramme of gold may produce a wire with a length of around 2 kilometers.Non metals are not ductile. Exception- Carbon fiber. It is used to make aircraft and spacecraft parts, racing car bodies, bicycle frames etc.
METALSNON-METALS
Malleability: Malleability is the ability of a substance to be beaten into thin sheets. Eg- Gold, Aluminium. Exception- Sodium, Potassium, Mercury, ZincNonmetals: are not malleable. We cannot make sheets with non-metals.
METALSNON-METALS
Brittleness: Brittleness refers to a material’s inability to deform due to its atomic microstructure. On applying force something break. Metals are generally hard but not Brittle. Exception: Zinc is a brittle metal.Solid nonmetals are generally Brittle. Examples- Graphite, coal Exception: Gases.
METALSNON-METALS
Conduction of heat and electricity Metals are good conductors of heat and electricity. Exception – Tungsten wireConduction of heat and electricity  Nonmetals are bad conductor of heat and electricity Exception – Gas carbon, Gas fiber, Graphite

Types Of Ions

  • Metals form positive charge ions called Cations.
    Metals have valence electrons = 1,2,3
  • Example:
    1. 11Na = 2,8,1
    Na –> Na+ + e

    2. 20Ca = 2,8,8,2
    Ca –> Ca+2 + 2e
  • Whereas, Non-metals forms negative charge ions called Anions.
    Non-metals have valence electrons = 4,5,6,7
  • Example:
    1. 9F = 2,7
    F + e –> F

    2. 17Cl = 2,8,7
    Cl + e –> Cl

Chemical Properties Of Metals

  • Reaction with oxygen
  • Not all metals react with the same level of reactivity.

Metal + Oxygen -> Metallic Oxide

(heat)

  • 2Mg + O₂ —> 2MgO

(room temp)

  • 4Na + O₂ ——> 2Na₂O

Reactivity Series of Metals

(From most reactive to least reactive)

Potassium (K)
Sodium (Na)
Calcium (Ca)
Magnesium (Mg)
Aluminium (Al)
Zinc (Zn)
Iron (Fe)
Lead (Pb)
Copper (Cu)
Silver (Ag)
Gold (Au)

Reactivity LevelMetals
Most ReactivePotassium (K)
Sodium (Na)
Calcium (Ca)
Moderately ReactiveMagnesium (Mg)
Aluminium (Al)
Zinc (Zn)
Iron (Fe)
Lead (Pb)
Reference ElementHydrogen (H)
Least ReactiveCopper (Cu)
Mercury (Hg)
Silver (Ag)
Gold (Au)

Chemical properties of Non-metals

  • Reaction with oxygen

Non-metal + Oxygen → Non-metallic Oxide

  • Examples:
  1. C + O₂ → CO₂
  2. S + O₂ → SO₂
  3. 2H₂ + O₂ → 2H₂O
  • Reaction with Salt Solutions

A more reactive non-metal displaces a less reactive non-metal from its salt solution.

For Example:

2NaBr(aq) + Cl2(g) –> NaCl(aq) + Br2
(Less reactive) (More reactive)

  • REACTION WITH ACID

Non-metals lack an excess of electrons to donate.

Hence, Non-metals do not generally react with acids because they are not easily capable of donating electrons to the hydrogen ions (H+) produced by the acids.

Chemical Properties of Metals

  • NATURE OF OXIDE

Metallic Oxide

Metallic oxides are of two types:

1. Basic Oxides

Examples:

  • Na₂O
  • CaO
  • MgO
    etc.
2. Amphoteric Oxides

Examples:

  • ZnO
  • PbO
  • Al₂O₃

Non-metallic Oxides

Non-metallic oxides are of two types:

1. Acidic Oxides

Examples:

  • CO₂
  • SO₂
  • P₂O₅

2. Neutral Oxides

Examples:

  • CO
  • NO
  • H₂O
    etc.
  • REACTION WITH WATER
React with Cold Water
  • Potassium (K)
  • Sodium (Na)
  • Calcium (Ca)

React with Hot Water or Steam
  • Magnesium (Mg) → reacts with hot water and steam

React with Steam
  • Aluminium (Al)
  • Zinc (Zn)
  • Iron (Fe)

No Reaction with Water or Steam
  • Lead (Pb)
  • Hydrogen (H)
  • Copper (Cu)
  • Mercury (Hg)
  • Silver (Ag)
  • Gold (Au)
  • Platinum (Pt)
  • Note:

Metal + H2O (water) –> Metallic hydroxide + H2(g)

Metal + H2O(steam) –> Metallic oxide + H2(g)

  • REACTION WITH WATER

Non–metals do not react with water (or steam) to evolve hydrogen gas. This is because non-metals cannot give electrons to reduce the hydrogen ions of water into hydrogen gas.

  • REACTION WITH ACID

Metal + Acid → Salt + Hydrogen gas
(Dilute acids; except nitric acid (HNO₃)

Examples:
  1. Zn + 2HCl (dilute) –> ZnCl2 (aq) + H2 (g)
  2. Zn + H2SO4 (dilute) –> ZnSO4 + H2(g)
  • HNO₃ is a strong oxidizing agent.
    When it reacts with a metal, it oxidizes the hydrogen gas and forms water (H₂O).
  • Exception:


Mg + HNO3 –> Mg(NO3)2 + H2

Mn + HNO3 –> Mn(NO3)2 + H2

  • AQUA REGIA

Aqua – regia is a freshly prepared mixture of 1 part of concentrated nitric acid and 3 parts of concentrated hydrochloric acid.

HNO3 + 3HCl –> NOCl + H2O + [Cl] (This can dissolve Au & Pt metal also.)

Au + 3[Cl] –> AuCl3

Pt + 4[Cl] –> PtCl4

  • Reaction with Solution of Other Metal

More reactive metal can displace less reactive metal from its salt’s solution.

  1. Fe + CuSO4 —-> FeSO4 + Cu
    (Grey) (Blue) (Colorless) (Brown colour)

2. Al + FeSO4 —> Al2(SO4)3 + Fe

  • Summary for chemical properties of metals
ElementsReaction with oxygenReaction with waterReaction with acids
1. K
2. Na
3. Ca
React with oxygen at ordinary temperature to form oxides.K and Na react vigorously with cold water Ca reacts moderately with cold water.K and Na react explosively with dilute acids to give hydrogen but Ca reacts less vigorously.
4. Mg
5. Al
6. Zn
7. Fe
Form oxides on heating, but Aluminium reacts with it at ordinary temperature.Mg reacts with hot water or steam; others react with steam only to from oxide and hydrogen.Mg, Al, Zn and Fe react moderately with acids to produce hydrogen.
8. Pb
9. Cu
10. Hg
From oxides on very strong heatingNo reaction with hot water or steam.Pb reacts with conc. HCL to give H_2,Cu and Hg do not react with dilute acids.
11. Ag
12. Au
13. Pt
Do not react with oxygen even on strong heatingNo reaction with hot water or steam.Do not react with dilute acids.
  • How do metals and non-metals react

Everyone desires stability in their lives.

For atoms, stability means achieving inert gas configuration.

A Chemical bond may be defined as the force of attraction between any two atoms, in a molecule, to maintain stability.

Types Of Bonding

Ionic Bond – Formed between metals and non-metals.

Covalent Bond – Bond formed between non-metals.

Electrovalent (Or Ionic Bond)

The chemical bond formation in this is due to the electrostatic force of attraction between a cation and an anion. It is called an electrovalent  (or ionic) bond.

Example:

Lets take the example for NaCl,
Here, Na is the metal and Cl is the non-metal.

11Na = 2,8,1 –> Na+= 2,8
17Cl = 2,8,7 –> Cl= 2,8

[Na]+[Cl] (Strong Electrostatic force of attraction exists between Na+ & Cl)

Characteristics Of Ionic Compounds

  • Physical state – They are generally crystalline solids because the force of attraction between the particles is more.
  • They have a high melting point and boiling point.
  • They are highly soluble in water because water molecule surrounds cation and anion. Also, Ionic compounds are insoluble in organic solvents for example – CCl4, CS2, C6H6, C6H5CH3
  • Note – Since water is a polar compound, hence ionic compounds are soluble in water.
  • Their density is generally more than the density of water.
  • In a fused state or in an aqueous solution, they are good conductors of electricity but in a solid state, they do not conduct electricity.
  • Ques – Why solid NaCl does not conduct electricity but molten or aqueous conduct electricity?
  • Ans – Solid NaCl does not conduct electricity because its ions are held tightly in a fixed position and cannot move to carry an electric current. However, when NaCl is melted or dissolved in water, its ions become free to move and can carry an electric current, making the solution conductive.

Why Ionic Compounds Are Stable

  • The electrostatic force of attraction between opposite charges is much higher, it makes the ionic compounds stable.
  • The strong ionic bond, regular crystal lattice structure, and high melting and boiling points all contribute to the stability of ionic compounds.

Redox Reaction

Oxidation and reduction occur simultaneously because the electrons lost by the reducing agent must be gained by the oxidizing agent.

Reducing agents are electron donors & Oxidizing agents are electron acceptors.

Metals are reducing agents       Non-metals are oxidizing agents

Oxidation ReactionReduction Reaction
1. Gain of oxygen1. Loss of oxygen
2. Loss of hydrogen2. Gain of hydrogen
3. Loss of electrons (e⁻)3. Gain of electrons (e⁻)
4. Increase in oxidation number (O.N / charge)4. Decrease in oxidation number (O.N / charge)

Example:

2K0+Cl20​→2K+Cl

Oxidation:

Potassium (K) loses one electron to form K⁺.
Oxidation number of potassium increases from 0 to +1.
Hence, oxidation occurs.

Reduction:

Chlorine (Cl₂) gains electrons to form Cl⁻.
Oxidation number of chlorine decreases from 0 to −1.
Hence, reduction occurs.

Reducing Agent (R.A.):

Potassium is the reducing agent because it donates electrons to chlorine.

Oxidizing Agent (O.A.):

Chlorine is the oxidizing agent because it accepts electrons from potassium.

COVALENT BOND

  • The Chemical bond formed by the mutual sharing of one or more pairs of electrons is called a covalent (molecular) bond and the compound formed due to this bond is called a covalent compound.

  • TYPES OF COVALENT BOND

Single Covalent Bond

Double Covalent Bond

Triple Covalent Bond

Type of Covalent BondElectrons SharedExamples
Single Covalent BondSharing of 1 e⁻ pairH–Cl, H–F
Double Covalent BondSharing of 2 e⁻ pairsO=O, H₂C=CH₂
Triple Covalent BondSharing of 3 e⁻ pairsN≡N, HC≡CH

Characteristics of covalent bond

  • They are generally gaseous or volatile liquids or soft solids because they have a weak intermolecular force of attraction.
  • Covalent compounds are volatile compounds with low melting and boiling point.
  • Insoluble in water, but soluble in organic solvents.
  • Lower density than water.
  • Poor conductors of electricity because they lack ions and only contain molecule.


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