CHEMICAL REACTIONS & EQUATIONS
1. Photosynthesis Reaction:
2. Formation of Slaked Lime
(it is also called Ca(OH)2, so don’t get confused)
3. Whitewashing of walls : Calcium hydroxide reacts slowly
with the carbon dioxide in air to form a thin layer of calcium
carbonate on the walls. Calcium carbonate is formed after
two to three days of white washing and gives a shiny finish
to the walls. It is interesting to note that the chemical
formula for marble is also CaCO3.
4. Decomposition Reaction:
5. Black & White Photography :
6. Displacement Reaction:
7. Double Displacement Reaction:
1.
2. Sodium chloride reacts with silver nitrate to form sodium nitrate and silver
chloride:
NaCl + AgNO3 → NaNO3 + AgCl
8. Redox Reaction:
9. Rusting of Iron:
10.
Corrosion of Silver :
Ag(s) + H2S(g) —> Ag2S(s) (Black Silver Sulphide)
11. Corrosion of Copper:
Cu(s) + H2O(l) + O2(g) + CO2(g) —---> Cu(OH)2.CuCO3
(Green colored basic copper Carbonate)
ACIDS, BASES & SALTS
1. Reaction of acids with metals: (i) Hydrochloric acid reacts
with zinc to form zinc chloride and hydrogen gas
2HCl + Zn → ZnCl2 + H2
(ii) Sulphuric acid reacts with iron to form iron(II) sulphate and
hydrogen gas:
H2SO4 + Fe → FeSO4 + H2
2. Reaction of acids with bases: (i) Hydrochloric acid reacts
with sodium hydroxide to form sodium chloride and water:
HCl + NaOH → NaCl + H2O
(ii). Nitric acid reacts with calcium hydroxide to form calcium
nitrate and water:
2HNO3 + Ca(OH)2 → Ca(NO3)2 + 2H2O
3. Reaction of acids with carbonates and bicarbonates:
(i). Hydrochloric acid reacts with sodium carbonate to form
sodium chloride, water, and carbon dioxide gas:
2HCl + Na2CO3 → 2NaCl + H2O + CO2
(ii). Acetic acid reacts with sodium bicarbonate to form sodium
acetate, water, and carbon dioxide gas:
CH3COOH + NaHCO3 → CH3COONa + H2O + CO2
4. Neutralization reactions:
i. Hydrochloric acid reacts with sodium hydroxide to form
sodium chloride and water:
HCl + NaOH → NaCl + H2O
5. Reaction of metal oxides with acids:
i. Copper(II) oxide reacts with hydrochloric acid to form
copper chloride and water:
CuO + 2HCl → CuCl2 + H2O
ii. Zinc oxide reacts with sulphuric acid to form zinc
sulphate and water:
6. Reaction of metal carbonates with acids:
i. Calcium carbonate reacts with hydrochloric acid to form
calcium chloride, water, and carbon dioxide gas:
CaCO3 + 2HCl → CaCl2 + H2O + CO2
7. Reaction of non-metal oxides with bases:
Carbon dioxide reacts with sodium hydroxide to form
sodium carbonate and water:
CO2 + 2NaOH → Na2CO3 + H2O
Sulphur dioxide reacts with calcium hydroxide to form
calcium sulphite and water:
SO2 + Ca(OH)2 → CaSO3 + H2O
8. Sodium Hydroxide (Chlor-Alkali Process):
9. Bleaching Powder :
CaoCl2 is bleaching powder
9. Baking Soda:
The chemical name of the compound is sodium hydrogen
carbonate (NaHCO3 ). It is produced using sodium chloride as
one of the raw materials.
Reaction happening during cooking :
9. Baking Powder:
10. Washing Soda:
Another chemical that can be obtained from sodium chloride is
Na2CO3 .10H2O (washing soda). Recrystallisation of sodium
carbonate gives washing soda. It is also a basic salt.
11. Plaster of Paris : On heating gypsum at 373 K, it loses water
molecules and becomes calcium sulphate hemihydrate
(CaSO4.1/2HO). It is plaster of Paris
METALS & NON-METALS
1. Metal & Oxygen reaction : Almost all metals combine with
oxygen to form metal oxides.
2. Amphoteric Oxides : Metal oxides are basic in nature. But
some metal oxides, such as aluminium oxide, zinc oxide,
etc., show both acidic as well as basic behaviour. Such
metal oxides which react with both acids as well as bases to
produce salts and water are known as amphoteric oxides.
3. Metal Oxides Soluble in Water : Most metal oxides are
insoluble in water but some of these dissolve in water to
form alkalis.
METAL + WATER REACTION
4. Potassium & Sodium - Potassium and sodium react
violently with cold water. The reaction is so violent and
exothermic that the evolved hydrogen immediately catches
fire.
5. Reaction of calcium with water is less violent:
Calcium starts floating because the bubbles of hydrogen
gas formed stick to the surface of the metal. Magnesium
does not react with cold water. It reacts with hot water to
form magnesium hydroxide and hydrogen. It also starts
floating due to the bubbles of hydrogen gas sticking to its
surface. Metals like aluminum, iron and zinc do not react
either with cold or hot water. But they react with steam to
form the metal oxide and hydrogen.
GOLD, SIlver, lead, copper don’t react with water at all.
—> Hydrogen gas is not evolved when a metal reacts with
nitric acid. It is because HNO3 is a strong oxidising agent. It
oxidizes the H2 produced to water and itself gets reduced to
any of the nitrogen oxides (N2O, NO, NO2). But magnesium
(Mg) and manganese (Mn) react with very dilute HNO3 to
evolve H2 gas.
6. Metal & Salt Solution Reaction:
Fe + CuSO4 —---> FeSO4 +Cu
7. Metals & Non - Metals Reaction:
EXTRACTION OF METALS
8. Extracting Metals Low in the Activity Series (MERCURY &
COPPER) -
9. Extracting Metals in the Middle of the Activity Series:
Activity series such as iron, zinc, lead, copper, etc., are
moderately reactive. These are usually present as sulphides
or carbonates in nature. It is easier to obtain a metal from its
oxide, as compared to its sulphides and carbonates.
PRIOR TO REDUCTION, metal sulphides and carbonates
must be converted into metal oxides.
Roasting : The sulphide ores are converted into oxides by
heating strongly in the presence of excess air.
Calcination : The carbonate ores are changed into oxides by
heating strongly in limited air.
The metal oxides are then reduced to the corresponding metals
by using suitable reducing agents such as carbon.
10. Highly Reactive metals are also used for reducing: The
highly reactive metals such as sodium, calcium, aluminium,
etc., are used as reducing agents because they can displace
metals of lower reactivity from their compounds. For
example, when manganese dioxide is heated with
aluminium powder, the following reaction takes place –
11. Thermite Reaction : The amount of heat evolved is so
large that the metals are produced in the molten state. In
fact, the reaction of iron(III) oxide (Fe2 O3) with aluminium is
used to join railway tracks or cracked machine parts.
12.
Electrolytic Refining:
13.
Alloys:
CARBON & IT’S COMPOUNDS
PLEASE READ THE ENTIRE CHAPTER, IT’S VEY IMPORANT!
1. Combustion :
(i) C + O2 → CO2 + heat and light
(ii) CH4 + O2 → CO2 + H2O + heat and light
(iii) CH3CH2OH + O2 → CO2 + H2O + heat and light
2. Oxidation : Alkaline potassium permanganate or acidified
potassium dichromate are oxidising alcohols to acids, that
is, adding oxygen to the starting material. Hence they are
known as oxidising agents.
3. Addition Reaction : Unsaturated hydrocarbons add
hydrogen in the presence of catalysts such as palladium or
nickel to give saturated hydrocarbons.. This reaction is
commonly used in the hydrogenation of vegetable oils
using a nickel catalyst. Vegetable oils generally have long
unsaturated carbon chains while animal fats have saturated
carbon chains.
(Catalyst meaning: they cause a reaction to occur or
proceed at a different rate without the reaction itself being
affected.)
Animal fats generally contain saturated fatty acids which are said
to be harmful for health. Oils containing unsaturated fatty acids
should be chosen for cooking.
4. Substitution Reaction :
CH4 + Cl2 → CH3Cl + HCl (in the presence of sunlight)
REACTIONS OF ETHANOL
1. Reactions with Sodium :
2. Reaction to give unsaturated hydrocarbon: Heating ethanol
at 443 K with excess concentrated sulphuric acid results in
the dehydration of ethanol to give ethene
REACTIONS OF ETHANOIC ACID
1. Esterification reaction: Esters are most commonly formed
by reaction of an acid and an alcohol. Ethanoic acid reacts
with absolute ethanol in the presence of an acid catalyst to
give an ester. Ester is sweet smelling
2. Saponification Reaction : . On treating with sodium
hydroxide, which is an alkali, the ester is converted back to
alcohol and sodium salt of carboxylic acid. This reaction is
known as saponification because it is used in the
preparation of soap. Soaps are sodium or potassium salts
of long chain carboxylic acid.
3. Reaction with Base:
4. Reaction with carbonates and hydrogencarbonates:
The salt produced is commonly called sodium acetate.
SOAPS & DETERGENTS