SlideShare a Scribd company logo
1 of 39
Chemical Reactions
and Equations
Class X – Science Chapter 1 Chemistry
Chemical Reactions
• The breaking and making of bonds between different
atoms to produce new substances is called
Chemical Reaction.
• There are two type of changes namely physical and
chemical changes.
o Melting of Ice (Physical Change)
o Rusting of Iron (Chemical Change)
o Formation of Curd (Chemical change)
Physical change Vs Chemical Change
• Any change that involves chemical changes is called
Chemical reaction.
Physical Change Chemical Change
Change is temporary Change is permanent
No new substance is formed.
There is change only in
physical properties.
New substances are formed
with entirely different physical
and chemical properties
Change can be reversed by
simple physical methods
Change cannot be reversed by
simple physical methods
Energy may or may not be
released or absorbed
Energy is released or absorbed
during chemical change
Chemical Equations
• The representation of chemical reactions in the form
of formulae of reactants and products separated by
an arrow mark is called Chemical Equation.
o Word Equation
Magnesium + Oxygen Magnesium Oxide
(Reactants) (Product)
LHS RHS
o Chemical Equation
Mg + O2 MgO
(Reactants) (Product)
LHS RHS
Balanced Equation
• The same number of atoms of each element on the
LHS (i.e. reactants) and RHS (i.e. products) of the
equation.
o Chemical Equation – Example 1
Mg + O2 MgO
LHS RHS
Mg  1
O  2
Mg  1
O  1
LHS RHS
Mg  1
O  2 x 1
Mg  1
O  1 x 2
Mg + O2 2MgO
Balancing of Equations
Mg + O2 2MgO
LHS RHS
Mg  1
O  2
Mg  2
O  2
LHS RHS
Mg  1 x 2
O  2
Mg  2 x 1
O  2
2 Mg + O2 2MgO
Balancing of Equations
o Chemical Equation – Example 2
Fe + H2O Fe3O4 + H2
LHS RHS
Fe  1
H  2
O  1
Fe  3
H  2
O  4
LHS RHS
Fe  1 x 3 = 3
H  2
O  1
Fe  3 x 1 = 3
H  2
O  4
3Fe + H2O Fe3O4 + H2
Balancing of Equations
3Fe + H2O Fe3O4 + H2
LHS RHS
Fe  3
H  8
O  4
Fe  3
H  2
O  4
LHS RHS
Fe  3
H  2
O  1 x 4 = 4
Fe  3
H  2
O  4 x 1 = 4
3Fe + 4H2O Fe3O4 + H2
Balancing of Equations
LHS RHS
Fe  3
H  8
O  4
Fe  3
H  8
O  4
Thus the equation is balanced!!!!
LHS RHS
Fe  3
H  8
O  4
Fe  3
H  2 x 4 = 8
O  4
3Fe + 4H2O Fe3O4 + 4H2
Informative Equation
• Informative Equation is the representation of
physical states using symbols like
Physical State Representation
Solid s
Liquid l
Gas g / ↑
Water soluble solution aq
Precipitate ↓
Reaction Conditions such as
Temperature, Pressure, Catalyst
Indicated above or
below the arrow
Heat Δ
Informative Equation
• Examples:
3Fe(s) + 4H2O (l) Fe3O4(s) + 4H2↑
CO (g) + 2H2 (g) 340 atm CH3OH (l)
6CO2 (aq) + 12H2O (l) Sunlight C6H12O6 (aq) + 6O2 (aq) + 6H2O (l)
Chlorophyll
Type of Reactions
• Combination
• Decomposition
• Displacement
• Double displacement
• Oxidation
• Reduction
• Redox Reaction
• Precipitation
• Exothermic reaction
• Endothermic reaction
Combination Reaction
• A reaction in which two or more reactants combine
to form a single product is called chemical
combination.
• Burning of coal:
C (s) + O2 (g) CO2 (g)
(Carbon) (Oxygen) (Carbon dioxide)
• Formation of Water from H2(g) and O2 (g)
2 H2 (g) + O2 (g) 2H2O (l)
(Hydrogen) (Oxygen) (Water)
• Formation of slaked lime:
CaO (s) + H2O(l) Ca(OH)2 (aq)
(Quick Lime) (Water) (Slaked Lime – Calcium Hydroxide)
Decomposition Reaction
• A reaction in which a single reactant breaks down to form
two or more products is known as decomposition
reaction.
• Three types of decomposition are thermal
decomposition, electrolytic decomposition and photolytic
decomposition.
• Thermal decomposition – Decomposition reaction taking place
in the presence of heat
2FeSO4 (s) Heat Fe2O3 + SO2 (g) + SO3 (g)
(Ferrous Sulphate) (Ferric Oxide) (Sulphur (Sulphur
dioxide) trioxide)
2CaCO3 (s) Heat CaO (s) + CO2 (g)
(Limestone) (Quick Lime) (Carbon dioxide)
2 Pb(NO3)2
Heat 2PbO + 4NO2 (g) + O2 (g)
(Lead Nitrate) (Lead Oxide0 (Nitrogen (Oxygen)
dioxide)
Decomposition Reaction
• Photolytic Decomposition – Decomposition reaction
taking place in the presence of light.
2AgCl (s) Sunlight 2Ag (s) + Cl2 (g)
(Silver Chloride) (Silver) (Chlorine)
2AgBr (s) Sunlight 2Ag (s) + Br2 (g)
(Silver Bromide) (Silver) (Bromine)
• Electrolytic Decomposition – Decomposition
reaction taking place in the presence of electricity.
2H2O (l) Electrolysis 2H2 (g) + O2 (g)
(Water) (Hydrogen) (Oxygen)
Displacement Reaction
• When a more reactive element displaces less reactive
element from its compound it is called displacement
reaction.
Fe(s) + CuSO4 (aq) FeSO4 (aq) + Cu(s)
(Iron) (Copper Sulphate) (Iron Sulphate) (Copper)
Zn(s) + CuSO4 (aq) ZnSO4 (aq) + Cu(s)
(Zinc) (Copper Sulphate) (Zinc Sulphate) (Copper)
Pb(s) + CuCl2 (aq) PbCl2 (aq) + Cu(s)
(Lead) (Copper Chloride) (Lead Chloride) (Copper)
Double Displacement Reaction
• The reaction in which two different ions or group of
atoms in the reactant molecules are displaced it is
called as double displacement reaction.
Na2SO4 (aq) + BaCl2 (aq) BaSO4 (s) + 2NaCl (aq)
(Sodium (Barium (Barium (Sodium
Sulphate) Chloride) Sulphate) Chloride)
Oxidation and Reduction
• The process of addition of oxygen to a substance or
removal of hydrogen from a substance is called
oxidation.
2Cu (s) + O2 (g) Heat 2CuO (s)
(Copper) (Oxygen) (Copper Oxide)
• The process of removal of oxygen from a substance
or addition of hydrogen to a substance is called
Reduction.
2CuO (s) + H2 (g) Heat Cu (s) + H2O (l)
(Copper Oxide) (Hydrogen) (Copper) (Water)
Redox Reaction
• The reactions in which oxidation and reduction takes
place simultaneously is called redox reaction.
Precipitation Reaction
• Chemical reaction which involves formation of water
insoluble precipitation is called precipitation
reaction.
Na2SO4 (aq) + BaCl2 (aq) BaSO4 (s) + 2NaCl (aq)
(Sodium (Barium (Barium (Sodium
Sulphate) Chloride) Sulphate) Chloride)
Exothermic Reaction
• Reactions that involve evolution of heat are called
exothermic reactions.
• Burning of Natural Gas
CH4 (g) + 2O2 (g) CO2 (g) + 2H2O (g) + Energy
(Natural (Oxygen) (Carbon (Water)
gas) dioxide)
• Decomposition of vegetable into compost is also an
example of an exothermic reaction.
Exothermic Reaction
• Respiration is an exothermic process.
• The food that we intake is broken down into simpler
substances such as carbohydrates, protein, fats
during digestion.
• Carbohydrates thus absorbed are broken down to
glucose.
• Glucose combines with oxygen in the cells of our
body and provides energy. This reaction is called
as respiration
C6H12O6 (aq) + 6O2 (aq) CO2 (g) + 2H2O (g) + Energy
(Glucose) (Oxygen) (Carbon (Water)
dioxide)
•
Endothermic Reaction
• Reactions which occur by the absorption of heat are
called endothermic reaction.
2FeSO4 (s) Heat Fe2O3 + SO2 (g) + SO3 (g)
(Ferrous Sulphate) (Ferric Oxide) (Sulphur (Sulphur
dioxide) trioxide)
2CaCO3 (s) Heat CaO (s) + CO2 (g)
(Limestone) (Quick Lime) (Carbon dioxide)
Rancidity
• The process of slow oxidation of oil and fat present in the
food materials resulting in the change of smell and taste
in them is called rancidity.
• Rancidity of food can be prevented
o By keeping food materials in air tight container.
o Refrigeration of cooked food at low temperature
o Packing of food items like potato chips in packs containing
nitrogen gas instead of air. It prevents oils and fats from
reacting with air.
o Avoid keeping the cooked food and food materials in direct
contact with air.
o By adding anti-oxidants e.g. BHA (Butrylated Hydroxy Anisole).
Corrosion
• The phenomenon in which metals are slowly eaten
away by the reaction of air, water, chemicals present
in the atmosphere is called Corrosion.
o E.g. Black coating on Silver and Green coating on Copper
• Rusting of Iron is due to corrosion. It can be
prevented:
o By Applying paint on Iron articles, rusting (Corrosion) can
be prevented.
o Paint does not allow oxygen and moisture to come in
contact with the surface of Iron.
Activity – 1.1
• What happens when heat is applied on Magnesium
Ribbon by burning it on Spirit Lamp?
Magnesium burns with dazzling light and substance formed is
Magnesium oxide.
2Mg (s) + O2 (g) 2 MgO (s)
Inference:
o It changes state from hard metal to Powder.
o Endothermic reaction.
o It is a combination reaction.
Activity – 1.2
• What do you observe when Lead Nitrate reacts with
Potassium Iodide solution?
Lead Nitrate reacts with potassium iodide to form Lead iodide
which is insoluble in water and yellow in color.
Pb(NO3)2 (aq) + 2KI (aq) PbI2 (s) ↓ + KNO3(aq)
(Yellow
Precipitate)
Inference:
o It changes state from liquid to solid.
o Double Displacement Reaction.
o Precipitation reaction.
Activity – 1.3
• Which gas will evolve when Zinc metal reacts with dilute
Hydrochloric acid? How will you identify the gas.
o When Zinc reacts with dilute Hydrochloric acid, Zinc chloride is
formed and bubbles of hydrogen gas are observed.
o Conical flask becomes hot.
Zn (s) + 2HCl (aq) ZnCl2 (aq) + H2 (g) + Δ
(Dilute)
Inference:
o Evolution of Hydrogen gas (evolves with a pop sound upon a
burning candle)
o Exothermic reaction.
o Oxidation reaction as Hydrogen is removed.
o It is also a Displacement Reaction.
Activity – 1.4a
• What happens when quick lime is mixed with water?
o Calcium Oxide (quick lime) reacts vigorously with water to
produce slaked lime (calcium hydroxide) releasing large
amount of heat.
CaO (s) + H2O (l) Ca(OH)2 (aq) + Δ
(Quick Lime) (Water) (Slaked Lime – Calcium Hydroxide)
Inference:
o Combination reaction.
o Exothermic reaction.
Activity – 1.4b
• What happens when Calcium Hydroxide reacts with
Carbon dioxide?
o Calcium Hydroxide reacts with Carbon dioxide to form
Calcium Carbonate and Water.
Ca(OH)2 (s) + CO2 (g) CaCO3 (s) + H2O (g)
Inference:
o This is a common reaction that occurs during Whitewash.
Lime water (Calcium Hydroxide) reacts with Carbon dioxide
in atmosphere to form thick coat of Calcium Carbonate.
Activity – 1.5
• What happens when ferrous sulphate crystals are heated
in a dry boiling tube over a burner?
o The green colour of ferrous sulphate crystals changes to
brownish-black ferric oxide and smell of burning sulphur
dioxide is observed.
2FeSO4 (s) Heat Fe2O3 (s) + SO2 (g) + SO3 (g)
(Ferrous Sulphate) (Ferric Oxide) (Sulphur (Sulphur
Green Brownish-black dioxide) trioxide)
Inference:
o Smell is due to burning Sulphur dioxide.
o Thermal Decomposition reaction.
o Endothermic reaction.
Activity – 1.6
• What happens when Lead Nitrate is heated in a
boiling tube over a burner?
o Pungent smelling, brown fumes are evolved due to NO2 gas
and brownish residue of lead oxide (PbO) is left.
2Pb(NO3)2 (s) Heat PbO (s) + 4NO2 (g) + O2 (g)
(Lead Nitrate) (Lead Oxide) (Nitrogen (Oxygen)
Brownish residue
Inference:
o Pungent smell and Brown fumes are due to Nitrogen dioxide
o Thermal Decomposition reaction.
o Endothermic reaction.
Activity – 1.7
• Electrolysis of water.
o When water is electrolysed, Hydrogen and Oxygen are
emitted.
2H2O (l) Electrolysis 2H2 (g) + O2 (g)
(Water) (Hydrogen) (Oxygen)
Inference:
o Volume of Hydrogen gas is twice the volume of Oxygen.
o One of the gases catches fire and burns with pop sound
indicating that it is Hydrogen.
o In other gas, candle burns brightly indicating that it is
oxygen.
o Electrolytic Decomposition reaction.
Activity – 1.8
• Why do we store Silver chloride in dark coloured
bottles?
o Silver chloride turns grey in sunlight because silver metal is
formed due to photolytic reaction and chlorine gas is
produced.
2AgCl (s) Sunlight 2Ag (s) + Cl2 (g)
Inference:
o Photolytic Decomposition reaction.
Activity – 1.9
• Why does the colour of Copper Sulphate solution
change when an iron nail is dipped in it?
o Iron being more reactive than Copper, displaces it there by
forming a iron sulphate and copper metal.
Fe (s) + CuSO4 (S) FeSO4 (s) + Cu (s)
(Iron) (Copper Sulphate) (Iron Sulphate) Copper
(Blue) (Green)
Inference:
o Color changes from blue to Green due to formation of Iron
sulphate.
o Displacement Reaction.
Activity – 1.10
• Aqueous solution of Sodium Chloride, Sodium Sulphate and
Calcium Chloride are taken in three separate test tubes. Using
aqueous barium chloride how do you identify sodium sulphate?
o When Sodium sulphate reacts with barium chloride, white
precipitate of barium sulphate is formed.
Na2SO4 (aq) + BaCl2 (aq) BaSO4 (s) ↓ + 2NaCl (s)
Inference:
o Sodium Chloride & Calcium Chloride do not react with Barium
Chloride. Hence solution remains clear.
o Upon reaction with Barium Chloride, Sodium Sulphate
produces Barium Sulphate, a white precipitate.
o This is a Double Displacement Reaction.
Activity – 1.11a
• Why does Copper acquire a green coat when exposed to air for
a long time?
o Green coating is formed in copper due to corrosion. Green
coating is a mixture of copper carbonate and copper
hydroxide.
2Cu + H2O + CO2 + O2 Cu(OH)2 + CuCO3
Inference:
o Copper on exposure to air reacts with gases and moisture
in air to form Copper hydroxide and Copper carbonate
Activity – 1.11b
• Why does Copper Powder turn black when heated ?
o The surface of copper powder on heating becomes black as
it reacts with Oxygen to produce Copper oxide.
2 Cu + O2 Heat 2 CuO
Inference:
o Copper Oxide formed due to combination of Copper and
Oxygen is black in color.
o Combination reaction
o Endothermic reaction
o Oxidation reaction.
Ncert  class 10 - science - chapter 1 - chemical reactions and equations

More Related Content

What's hot

How do organisms reproduce.ppt
How do organisms reproduce.pptHow do organisms reproduce.ppt
How do organisms reproduce.ppt
Vijaya Saran
 

What's hot (20)

Carbon and Its Compound
Carbon and Its CompoundCarbon and Its Compound
Carbon and Its Compound
 
Electricity ppt for class 10
Electricity ppt for class 10Electricity ppt for class 10
Electricity ppt for class 10
 
Acids, Bases and Salts Class - 10th
Acids, Bases and Salts Class - 10thAcids, Bases and Salts Class - 10th
Acids, Bases and Salts Class - 10th
 
Control and coordination.ppt
Control and coordination.pptControl and coordination.ppt
Control and coordination.ppt
 
Life processes.ppt
Life processes.pptLife processes.ppt
Life processes.ppt
 
force and laws of motion
force and laws of motionforce and laws of motion
force and laws of motion
 
Light human eye and the colourful world
Light human eye and the colourful worldLight human eye and the colourful world
Light human eye and the colourful world
 
Carbon and its compounds
Carbon and its compoundsCarbon and its compounds
Carbon and its compounds
 
Is matter around us pure
Is matter around us pureIs matter around us pure
Is matter around us pure
 
structure of the atom
 structure of the atom structure of the atom
structure of the atom
 
Chapter acids, bases and salts(class 10)
Chapter   acids, bases and salts(class 10)Chapter   acids, bases and salts(class 10)
Chapter acids, bases and salts(class 10)
 
gravitation
gravitationgravitation
gravitation
 
matter in our surroundings
matter in our surroundingsmatter in our surroundings
matter in our surroundings
 
Our Environment Class - 10th
Our Environment Class - 10thOur Environment Class - 10th
Our Environment Class - 10th
 
Structure of atom ppt by shiva prasad class 9th a
Structure of atom ppt by shiva prasad class 9th aStructure of atom ppt by shiva prasad class 9th a
Structure of atom ppt by shiva prasad class 9th a
 
CHEMICAL REACTIONS AND EQUATIONS
CHEMICAL REACTIONS AND EQUATIONSCHEMICAL REACTIONS AND EQUATIONS
CHEMICAL REACTIONS AND EQUATIONS
 
Chapter 4 metals and non-metals (class-8) CBSE
Chapter 4 metals and non-metals (class-8) CBSEChapter 4 metals and non-metals (class-8) CBSE
Chapter 4 metals and non-metals (class-8) CBSE
 
How do organisms reproduce.ppt
How do organisms reproduce.pptHow do organisms reproduce.ppt
How do organisms reproduce.ppt
 
Magnetic Effects of Electric Current
Magnetic Effects of Electric CurrentMagnetic Effects of Electric Current
Magnetic Effects of Electric Current
 
combustion and flame
combustion and flamecombustion and flame
combustion and flame
 

Similar to Ncert class 10 - science - chapter 1 - chemical reactions and equations

ncert-class10-science-chapter1-chemicalreactionsandequations-200522140131.pptx
ncert-class10-science-chapter1-chemicalreactionsandequations-200522140131.pptxncert-class10-science-chapter1-chemicalreactionsandequations-200522140131.pptx
ncert-class10-science-chapter1-chemicalreactionsandequations-200522140131.pptx
SanyaGulati16
 
Chapter 8.2 : Types of Chemical Reactions
Chapter 8.2 : Types of Chemical ReactionsChapter 8.2 : Types of Chemical Reactions
Chapter 8.2 : Types of Chemical Reactions
Chris Foltz
 
Chemical Reactions 1196945876279030 3
Chemical Reactions 1196945876279030 3Chemical Reactions 1196945876279030 3
Chemical Reactions 1196945876279030 3
Laura Verastegui
 
Chapter 8: Reactions in Aqueous Solution
Chapter 8: Reactions in Aqueous SolutionChapter 8: Reactions in Aqueous Solution
Chapter 8: Reactions in Aqueous Solution
Melissa McDonald
 
Chemical Reactions
Chemical ReactionsChemical Reactions
Chemical Reactions
guestffe6a0
 
PHYSICAL AND CHEMICAL CHANGES CLASS VII CH NO.06 -SLIDE SHOW.pptx
PHYSICAL AND CHEMICAL CHANGES CLASS VII CH NO.06 -SLIDE SHOW.pptxPHYSICAL AND CHEMICAL CHANGES CLASS VII CH NO.06 -SLIDE SHOW.pptx
PHYSICAL AND CHEMICAL CHANGES CLASS VII CH NO.06 -SLIDE SHOW.pptx
30Hrisheek
 

Similar to Ncert class 10 - science - chapter 1 - chemical reactions and equations (20)

ncert-class10-science-chapter1-chemicalreactionsandequations-200522140131.pptx
ncert-class10-science-chapter1-chemicalreactionsandequations-200522140131.pptxncert-class10-science-chapter1-chemicalreactionsandequations-200522140131.pptx
ncert-class10-science-chapter1-chemicalreactionsandequations-200522140131.pptx
 
Basics of Chemical Reactions
Basics of Chemical ReactionsBasics of Chemical Reactions
Basics of Chemical Reactions
 
CBSE CLASS 10 CHEMISTRY CHAPTER 1 CHEMICAL REACTIONS AND EQUATIONS PART 2 TYP...
CBSE CLASS 10 CHEMISTRY CHAPTER 1 CHEMICAL REACTIONS AND EQUATIONS PART 2 TYP...CBSE CLASS 10 CHEMISTRY CHAPTER 1 CHEMICAL REACTIONS AND EQUATIONS PART 2 TYP...
CBSE CLASS 10 CHEMISTRY CHAPTER 1 CHEMICAL REACTIONS AND EQUATIONS PART 2 TYP...
 
ch.-1 chemical reactions and equations .pptx
ch.-1 chemical reactions and equations .pptxch.-1 chemical reactions and equations .pptx
ch.-1 chemical reactions and equations .pptx
 
Chapter 8.2 : Types of Chemical Reactions
Chapter 8.2 : Types of Chemical ReactionsChapter 8.2 : Types of Chemical Reactions
Chapter 8.2 : Types of Chemical Reactions
 
Chemical reactions and Equations PPT.pptx
Chemical reactions and Equations PPT.pptxChemical reactions and Equations PPT.pptx
Chemical reactions and Equations PPT.pptx
 
Chemical Reactions 1196945876279030 3
Chemical Reactions 1196945876279030 3Chemical Reactions 1196945876279030 3
Chemical Reactions 1196945876279030 3
 
Std 10, Chapter 2-Chemical Reactions
Std 10, Chapter 2-Chemical ReactionsStd 10, Chapter 2-Chemical Reactions
Std 10, Chapter 2-Chemical Reactions
 
Chemical reactions and equations
Chemical reactions and equationsChemical reactions and equations
Chemical reactions and equations
 
Chemical reactions and equations
Chemical reactions and equationsChemical reactions and equations
Chemical reactions and equations
 
Chapter 8: Reactions in Aqueous Solution
Chapter 8: Reactions in Aqueous SolutionChapter 8: Reactions in Aqueous Solution
Chapter 8: Reactions in Aqueous Solution
 
Chapter 4 notes
Chapter 4 notes  Chapter 4 notes
Chapter 4 notes
 
Chemical Reactions
Chemical ReactionsChemical Reactions
Chemical Reactions
 
Chemical reaction and equation class x
Chemical reaction and equation class xChemical reaction and equation class x
Chemical reaction and equation class x
 
Sistem karbonat
Sistem karbonatSistem karbonat
Sistem karbonat
 
PHYSICAL AND CHEMICAL CHANGES CLASS VII CH NO.06 -SLIDE SHOW.pptx
PHYSICAL AND CHEMICAL CHANGES CLASS VII CH NO.06 -SLIDE SHOW.pptxPHYSICAL AND CHEMICAL CHANGES CLASS VII CH NO.06 -SLIDE SHOW.pptx
PHYSICAL AND CHEMICAL CHANGES CLASS VII CH NO.06 -SLIDE SHOW.pptx
 
3 acid base reactions
3   acid base reactions3   acid base reactions
3 acid base reactions
 
Chemical reaction and equation
Chemical reaction and equationChemical reaction and equation
Chemical reaction and equation
 
Chemical reactions and equations Class 10
Chemical reactions  and equations Class 10Chemical reactions  and equations Class 10
Chemical reactions and equations Class 10
 
Class 10 l Science l Chemistry l Lesson 1: Chemical equations and reactions
Class 10 l Science l Chemistry l Lesson 1: Chemical equations and reactionsClass 10 l Science l Chemistry l Lesson 1: Chemical equations and reactions
Class 10 l Science l Chemistry l Lesson 1: Chemical equations and reactions
 

Recently uploaded

會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文
會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文
會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文
中 央社
 
The basics of sentences session 4pptx.pptx
The basics of sentences session 4pptx.pptxThe basics of sentences session 4pptx.pptx
The basics of sentences session 4pptx.pptx
heathfieldcps1
 

Recently uploaded (20)

Envelope of Discrepancy in Orthodontics: Enhancing Precision in Treatment
 Envelope of Discrepancy in Orthodontics: Enhancing Precision in Treatment Envelope of Discrepancy in Orthodontics: Enhancing Precision in Treatment
Envelope of Discrepancy in Orthodontics: Enhancing Precision in Treatment
 
How to Manage Notification Preferences in the Odoo 17
How to Manage Notification Preferences in the Odoo 17How to Manage Notification Preferences in the Odoo 17
How to Manage Notification Preferences in the Odoo 17
 
INU_CAPSTONEDESIGN_비밀번호486_업로드용 발표자료.pdf
INU_CAPSTONEDESIGN_비밀번호486_업로드용 발표자료.pdfINU_CAPSTONEDESIGN_비밀번호486_업로드용 발표자료.pdf
INU_CAPSTONEDESIGN_비밀번호486_업로드용 발표자료.pdf
 
Exploring Gemini AI and Integration with MuleSoft | MuleSoft Mysore Meetup #45
Exploring Gemini AI and Integration with MuleSoft | MuleSoft Mysore Meetup #45Exploring Gemini AI and Integration with MuleSoft | MuleSoft Mysore Meetup #45
Exploring Gemini AI and Integration with MuleSoft | MuleSoft Mysore Meetup #45
 
ĐỀ THAM KHẢO KÌ THI TUYỂN SINH VÀO LỚP 10 MÔN TIẾNG ANH FORM 50 CÂU TRẮC NGHI...
ĐỀ THAM KHẢO KÌ THI TUYỂN SINH VÀO LỚP 10 MÔN TIẾNG ANH FORM 50 CÂU TRẮC NGHI...ĐỀ THAM KHẢO KÌ THI TUYỂN SINH VÀO LỚP 10 MÔN TIẾNG ANH FORM 50 CÂU TRẮC NGHI...
ĐỀ THAM KHẢO KÌ THI TUYỂN SINH VÀO LỚP 10 MÔN TIẾNG ANH FORM 50 CÂU TRẮC NGHI...
 
Word Stress rules esl .pptx
Word Stress rules esl               .pptxWord Stress rules esl               .pptx
Word Stress rules esl .pptx
 
2024_Student Session 2_ Set Plan Preparation.pptx
2024_Student Session 2_ Set Plan Preparation.pptx2024_Student Session 2_ Set Plan Preparation.pptx
2024_Student Session 2_ Set Plan Preparation.pptx
 
Pragya Champions Chalice 2024 Prelims & Finals Q/A set, General Quiz
Pragya Champions Chalice 2024 Prelims & Finals Q/A set, General QuizPragya Champions Chalice 2024 Prelims & Finals Q/A set, General Quiz
Pragya Champions Chalice 2024 Prelims & Finals Q/A set, General Quiz
 
會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文
會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文
會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文會考英文
 
The basics of sentences session 4pptx.pptx
The basics of sentences session 4pptx.pptxThe basics of sentences session 4pptx.pptx
The basics of sentences session 4pptx.pptx
 
Danh sách HSG Bộ môn cấp trường - Cấp THPT.pdf
Danh sách HSG Bộ môn cấp trường - Cấp THPT.pdfDanh sách HSG Bộ môn cấp trường - Cấp THPT.pdf
Danh sách HSG Bộ môn cấp trường - Cấp THPT.pdf
 
The Last Leaf, a short story by O. Henry
The Last Leaf, a short story by O. HenryThe Last Leaf, a short story by O. Henry
The Last Leaf, a short story by O. Henry
 
BỘ LUYỆN NGHE TIẾNG ANH 8 GLOBAL SUCCESS CẢ NĂM (GỒM 12 UNITS, MỖI UNIT GỒM 3...
BỘ LUYỆN NGHE TIẾNG ANH 8 GLOBAL SUCCESS CẢ NĂM (GỒM 12 UNITS, MỖI UNIT GỒM 3...BỘ LUYỆN NGHE TIẾNG ANH 8 GLOBAL SUCCESS CẢ NĂM (GỒM 12 UNITS, MỖI UNIT GỒM 3...
BỘ LUYỆN NGHE TIẾNG ANH 8 GLOBAL SUCCESS CẢ NĂM (GỒM 12 UNITS, MỖI UNIT GỒM 3...
 
Essential Safety precautions during monsoon season
Essential Safety precautions during monsoon seasonEssential Safety precautions during monsoon season
Essential Safety precautions during monsoon season
 
Incoming and Outgoing Shipments in 2 STEPS Using Odoo 17
Incoming and Outgoing Shipments in 2 STEPS Using Odoo 17Incoming and Outgoing Shipments in 2 STEPS Using Odoo 17
Incoming and Outgoing Shipments in 2 STEPS Using Odoo 17
 
The Ball Poem- John Berryman_20240518_001617_0000.pptx
The Ball Poem- John Berryman_20240518_001617_0000.pptxThe Ball Poem- John Berryman_20240518_001617_0000.pptx
The Ball Poem- John Berryman_20240518_001617_0000.pptx
 
How to Analyse Profit of a Sales Order in Odoo 17
How to Analyse Profit of a Sales Order in Odoo 17How to Analyse Profit of a Sales Order in Odoo 17
How to Analyse Profit of a Sales Order in Odoo 17
 
size separation d pharm 1st year pharmaceutics
size separation d pharm 1st year pharmaceuticssize separation d pharm 1st year pharmaceutics
size separation d pharm 1st year pharmaceutics
 
Capitol Tech Univ Doctoral Presentation -May 2024
Capitol Tech Univ Doctoral Presentation -May 2024Capitol Tech Univ Doctoral Presentation -May 2024
Capitol Tech Univ Doctoral Presentation -May 2024
 
Championnat de France de Tennis de table/
Championnat de France de Tennis de table/Championnat de France de Tennis de table/
Championnat de France de Tennis de table/
 

Ncert class 10 - science - chapter 1 - chemical reactions and equations

  • 1. Chemical Reactions and Equations Class X – Science Chapter 1 Chemistry
  • 2. Chemical Reactions • The breaking and making of bonds between different atoms to produce new substances is called Chemical Reaction. • There are two type of changes namely physical and chemical changes. o Melting of Ice (Physical Change) o Rusting of Iron (Chemical Change) o Formation of Curd (Chemical change)
  • 3. Physical change Vs Chemical Change • Any change that involves chemical changes is called Chemical reaction. Physical Change Chemical Change Change is temporary Change is permanent No new substance is formed. There is change only in physical properties. New substances are formed with entirely different physical and chemical properties Change can be reversed by simple physical methods Change cannot be reversed by simple physical methods Energy may or may not be released or absorbed Energy is released or absorbed during chemical change
  • 4. Chemical Equations • The representation of chemical reactions in the form of formulae of reactants and products separated by an arrow mark is called Chemical Equation. o Word Equation Magnesium + Oxygen Magnesium Oxide (Reactants) (Product) LHS RHS o Chemical Equation Mg + O2 MgO (Reactants) (Product) LHS RHS
  • 5. Balanced Equation • The same number of atoms of each element on the LHS (i.e. reactants) and RHS (i.e. products) of the equation. o Chemical Equation – Example 1 Mg + O2 MgO LHS RHS Mg  1 O  2 Mg  1 O  1 LHS RHS Mg  1 O  2 x 1 Mg  1 O  1 x 2 Mg + O2 2MgO
  • 6. Balancing of Equations Mg + O2 2MgO LHS RHS Mg  1 O  2 Mg  2 O  2 LHS RHS Mg  1 x 2 O  2 Mg  2 x 1 O  2 2 Mg + O2 2MgO
  • 7. Balancing of Equations o Chemical Equation – Example 2 Fe + H2O Fe3O4 + H2 LHS RHS Fe  1 H  2 O  1 Fe  3 H  2 O  4 LHS RHS Fe  1 x 3 = 3 H  2 O  1 Fe  3 x 1 = 3 H  2 O  4 3Fe + H2O Fe3O4 + H2
  • 8. Balancing of Equations 3Fe + H2O Fe3O4 + H2 LHS RHS Fe  3 H  8 O  4 Fe  3 H  2 O  4 LHS RHS Fe  3 H  2 O  1 x 4 = 4 Fe  3 H  2 O  4 x 1 = 4 3Fe + 4H2O Fe3O4 + H2
  • 9. Balancing of Equations LHS RHS Fe  3 H  8 O  4 Fe  3 H  8 O  4 Thus the equation is balanced!!!! LHS RHS Fe  3 H  8 O  4 Fe  3 H  2 x 4 = 8 O  4 3Fe + 4H2O Fe3O4 + 4H2
  • 10. Informative Equation • Informative Equation is the representation of physical states using symbols like Physical State Representation Solid s Liquid l Gas g / ↑ Water soluble solution aq Precipitate ↓ Reaction Conditions such as Temperature, Pressure, Catalyst Indicated above or below the arrow Heat Δ
  • 11. Informative Equation • Examples: 3Fe(s) + 4H2O (l) Fe3O4(s) + 4H2↑ CO (g) + 2H2 (g) 340 atm CH3OH (l) 6CO2 (aq) + 12H2O (l) Sunlight C6H12O6 (aq) + 6O2 (aq) + 6H2O (l) Chlorophyll
  • 12. Type of Reactions • Combination • Decomposition • Displacement • Double displacement • Oxidation • Reduction • Redox Reaction • Precipitation • Exothermic reaction • Endothermic reaction
  • 13. Combination Reaction • A reaction in which two or more reactants combine to form a single product is called chemical combination. • Burning of coal: C (s) + O2 (g) CO2 (g) (Carbon) (Oxygen) (Carbon dioxide) • Formation of Water from H2(g) and O2 (g) 2 H2 (g) + O2 (g) 2H2O (l) (Hydrogen) (Oxygen) (Water) • Formation of slaked lime: CaO (s) + H2O(l) Ca(OH)2 (aq) (Quick Lime) (Water) (Slaked Lime – Calcium Hydroxide)
  • 14. Decomposition Reaction • A reaction in which a single reactant breaks down to form two or more products is known as decomposition reaction. • Three types of decomposition are thermal decomposition, electrolytic decomposition and photolytic decomposition. • Thermal decomposition – Decomposition reaction taking place in the presence of heat 2FeSO4 (s) Heat Fe2O3 + SO2 (g) + SO3 (g) (Ferrous Sulphate) (Ferric Oxide) (Sulphur (Sulphur dioxide) trioxide) 2CaCO3 (s) Heat CaO (s) + CO2 (g) (Limestone) (Quick Lime) (Carbon dioxide) 2 Pb(NO3)2 Heat 2PbO + 4NO2 (g) + O2 (g) (Lead Nitrate) (Lead Oxide0 (Nitrogen (Oxygen) dioxide)
  • 15. Decomposition Reaction • Photolytic Decomposition – Decomposition reaction taking place in the presence of light. 2AgCl (s) Sunlight 2Ag (s) + Cl2 (g) (Silver Chloride) (Silver) (Chlorine) 2AgBr (s) Sunlight 2Ag (s) + Br2 (g) (Silver Bromide) (Silver) (Bromine) • Electrolytic Decomposition – Decomposition reaction taking place in the presence of electricity. 2H2O (l) Electrolysis 2H2 (g) + O2 (g) (Water) (Hydrogen) (Oxygen)
  • 16. Displacement Reaction • When a more reactive element displaces less reactive element from its compound it is called displacement reaction. Fe(s) + CuSO4 (aq) FeSO4 (aq) + Cu(s) (Iron) (Copper Sulphate) (Iron Sulphate) (Copper) Zn(s) + CuSO4 (aq) ZnSO4 (aq) + Cu(s) (Zinc) (Copper Sulphate) (Zinc Sulphate) (Copper) Pb(s) + CuCl2 (aq) PbCl2 (aq) + Cu(s) (Lead) (Copper Chloride) (Lead Chloride) (Copper)
  • 17. Double Displacement Reaction • The reaction in which two different ions or group of atoms in the reactant molecules are displaced it is called as double displacement reaction. Na2SO4 (aq) + BaCl2 (aq) BaSO4 (s) + 2NaCl (aq) (Sodium (Barium (Barium (Sodium Sulphate) Chloride) Sulphate) Chloride)
  • 18. Oxidation and Reduction • The process of addition of oxygen to a substance or removal of hydrogen from a substance is called oxidation. 2Cu (s) + O2 (g) Heat 2CuO (s) (Copper) (Oxygen) (Copper Oxide) • The process of removal of oxygen from a substance or addition of hydrogen to a substance is called Reduction. 2CuO (s) + H2 (g) Heat Cu (s) + H2O (l) (Copper Oxide) (Hydrogen) (Copper) (Water)
  • 19. Redox Reaction • The reactions in which oxidation and reduction takes place simultaneously is called redox reaction.
  • 20. Precipitation Reaction • Chemical reaction which involves formation of water insoluble precipitation is called precipitation reaction. Na2SO4 (aq) + BaCl2 (aq) BaSO4 (s) + 2NaCl (aq) (Sodium (Barium (Barium (Sodium Sulphate) Chloride) Sulphate) Chloride)
  • 21. Exothermic Reaction • Reactions that involve evolution of heat are called exothermic reactions. • Burning of Natural Gas CH4 (g) + 2O2 (g) CO2 (g) + 2H2O (g) + Energy (Natural (Oxygen) (Carbon (Water) gas) dioxide) • Decomposition of vegetable into compost is also an example of an exothermic reaction.
  • 22. Exothermic Reaction • Respiration is an exothermic process. • The food that we intake is broken down into simpler substances such as carbohydrates, protein, fats during digestion. • Carbohydrates thus absorbed are broken down to glucose. • Glucose combines with oxygen in the cells of our body and provides energy. This reaction is called as respiration C6H12O6 (aq) + 6O2 (aq) CO2 (g) + 2H2O (g) + Energy (Glucose) (Oxygen) (Carbon (Water) dioxide) •
  • 23. Endothermic Reaction • Reactions which occur by the absorption of heat are called endothermic reaction. 2FeSO4 (s) Heat Fe2O3 + SO2 (g) + SO3 (g) (Ferrous Sulphate) (Ferric Oxide) (Sulphur (Sulphur dioxide) trioxide) 2CaCO3 (s) Heat CaO (s) + CO2 (g) (Limestone) (Quick Lime) (Carbon dioxide)
  • 24. Rancidity • The process of slow oxidation of oil and fat present in the food materials resulting in the change of smell and taste in them is called rancidity. • Rancidity of food can be prevented o By keeping food materials in air tight container. o Refrigeration of cooked food at low temperature o Packing of food items like potato chips in packs containing nitrogen gas instead of air. It prevents oils and fats from reacting with air. o Avoid keeping the cooked food and food materials in direct contact with air. o By adding anti-oxidants e.g. BHA (Butrylated Hydroxy Anisole).
  • 25. Corrosion • The phenomenon in which metals are slowly eaten away by the reaction of air, water, chemicals present in the atmosphere is called Corrosion. o E.g. Black coating on Silver and Green coating on Copper • Rusting of Iron is due to corrosion. It can be prevented: o By Applying paint on Iron articles, rusting (Corrosion) can be prevented. o Paint does not allow oxygen and moisture to come in contact with the surface of Iron.
  • 26. Activity – 1.1 • What happens when heat is applied on Magnesium Ribbon by burning it on Spirit Lamp? Magnesium burns with dazzling light and substance formed is Magnesium oxide. 2Mg (s) + O2 (g) 2 MgO (s) Inference: o It changes state from hard metal to Powder. o Endothermic reaction. o It is a combination reaction.
  • 27. Activity – 1.2 • What do you observe when Lead Nitrate reacts with Potassium Iodide solution? Lead Nitrate reacts with potassium iodide to form Lead iodide which is insoluble in water and yellow in color. Pb(NO3)2 (aq) + 2KI (aq) PbI2 (s) ↓ + KNO3(aq) (Yellow Precipitate) Inference: o It changes state from liquid to solid. o Double Displacement Reaction. o Precipitation reaction.
  • 28. Activity – 1.3 • Which gas will evolve when Zinc metal reacts with dilute Hydrochloric acid? How will you identify the gas. o When Zinc reacts with dilute Hydrochloric acid, Zinc chloride is formed and bubbles of hydrogen gas are observed. o Conical flask becomes hot. Zn (s) + 2HCl (aq) ZnCl2 (aq) + H2 (g) + Δ (Dilute) Inference: o Evolution of Hydrogen gas (evolves with a pop sound upon a burning candle) o Exothermic reaction. o Oxidation reaction as Hydrogen is removed. o It is also a Displacement Reaction.
  • 29. Activity – 1.4a • What happens when quick lime is mixed with water? o Calcium Oxide (quick lime) reacts vigorously with water to produce slaked lime (calcium hydroxide) releasing large amount of heat. CaO (s) + H2O (l) Ca(OH)2 (aq) + Δ (Quick Lime) (Water) (Slaked Lime – Calcium Hydroxide) Inference: o Combination reaction. o Exothermic reaction.
  • 30. Activity – 1.4b • What happens when Calcium Hydroxide reacts with Carbon dioxide? o Calcium Hydroxide reacts with Carbon dioxide to form Calcium Carbonate and Water. Ca(OH)2 (s) + CO2 (g) CaCO3 (s) + H2O (g) Inference: o This is a common reaction that occurs during Whitewash. Lime water (Calcium Hydroxide) reacts with Carbon dioxide in atmosphere to form thick coat of Calcium Carbonate.
  • 31. Activity – 1.5 • What happens when ferrous sulphate crystals are heated in a dry boiling tube over a burner? o The green colour of ferrous sulphate crystals changes to brownish-black ferric oxide and smell of burning sulphur dioxide is observed. 2FeSO4 (s) Heat Fe2O3 (s) + SO2 (g) + SO3 (g) (Ferrous Sulphate) (Ferric Oxide) (Sulphur (Sulphur Green Brownish-black dioxide) trioxide) Inference: o Smell is due to burning Sulphur dioxide. o Thermal Decomposition reaction. o Endothermic reaction.
  • 32. Activity – 1.6 • What happens when Lead Nitrate is heated in a boiling tube over a burner? o Pungent smelling, brown fumes are evolved due to NO2 gas and brownish residue of lead oxide (PbO) is left. 2Pb(NO3)2 (s) Heat PbO (s) + 4NO2 (g) + O2 (g) (Lead Nitrate) (Lead Oxide) (Nitrogen (Oxygen) Brownish residue Inference: o Pungent smell and Brown fumes are due to Nitrogen dioxide o Thermal Decomposition reaction. o Endothermic reaction.
  • 33. Activity – 1.7 • Electrolysis of water. o When water is electrolysed, Hydrogen and Oxygen are emitted. 2H2O (l) Electrolysis 2H2 (g) + O2 (g) (Water) (Hydrogen) (Oxygen) Inference: o Volume of Hydrogen gas is twice the volume of Oxygen. o One of the gases catches fire and burns with pop sound indicating that it is Hydrogen. o In other gas, candle burns brightly indicating that it is oxygen. o Electrolytic Decomposition reaction.
  • 34. Activity – 1.8 • Why do we store Silver chloride in dark coloured bottles? o Silver chloride turns grey in sunlight because silver metal is formed due to photolytic reaction and chlorine gas is produced. 2AgCl (s) Sunlight 2Ag (s) + Cl2 (g) Inference: o Photolytic Decomposition reaction.
  • 35. Activity – 1.9 • Why does the colour of Copper Sulphate solution change when an iron nail is dipped in it? o Iron being more reactive than Copper, displaces it there by forming a iron sulphate and copper metal. Fe (s) + CuSO4 (S) FeSO4 (s) + Cu (s) (Iron) (Copper Sulphate) (Iron Sulphate) Copper (Blue) (Green) Inference: o Color changes from blue to Green due to formation of Iron sulphate. o Displacement Reaction.
  • 36. Activity – 1.10 • Aqueous solution of Sodium Chloride, Sodium Sulphate and Calcium Chloride are taken in three separate test tubes. Using aqueous barium chloride how do you identify sodium sulphate? o When Sodium sulphate reacts with barium chloride, white precipitate of barium sulphate is formed. Na2SO4 (aq) + BaCl2 (aq) BaSO4 (s) ↓ + 2NaCl (s) Inference: o Sodium Chloride & Calcium Chloride do not react with Barium Chloride. Hence solution remains clear. o Upon reaction with Barium Chloride, Sodium Sulphate produces Barium Sulphate, a white precipitate. o This is a Double Displacement Reaction.
  • 37. Activity – 1.11a • Why does Copper acquire a green coat when exposed to air for a long time? o Green coating is formed in copper due to corrosion. Green coating is a mixture of copper carbonate and copper hydroxide. 2Cu + H2O + CO2 + O2 Cu(OH)2 + CuCO3 Inference: o Copper on exposure to air reacts with gases and moisture in air to form Copper hydroxide and Copper carbonate
  • 38. Activity – 1.11b • Why does Copper Powder turn black when heated ? o The surface of copper powder on heating becomes black as it reacts with Oxygen to produce Copper oxide. 2 Cu + O2 Heat 2 CuO Inference: o Copper Oxide formed due to combination of Copper and Oxygen is black in color. o Combination reaction o Endothermic reaction o Oxidation reaction.