| Name of Carbonate | Formula |
| Ammonium Carbonate | (NH4)2 CO3 |
| Sodium Carbonate | Na2CO3 |
| Potassium Carbonate | K2CO3 |
| Calcium Carbonate | CaCO3 |
| Magnesium Carbonate | MgCO3 |
| Aluminium Carbonate | Al2(CO3)3 |
| Zinc Carbonate | ZnCO3 |
| Iron Carbonate | FeCO3 |
| Lead Carbonate | PbCO3 |
| Copper Carbonate | CuCO3 |
Carbonates
Sulphates
| Name Of Sulphate | Formula |
| Ammonium Sulphate | (NH4)2SO4 |
| Sodium Sulphate | Na2SO4 |
| Potassium Sulphate | K2SO4 |
| Calcium Sulphate | CaSO4 |
| Magnesium Sulphate | MgSO4 |
| Zinc Sulphate | ZnSO4 |
| Aluminium Sulphate | Al2(SO4)3 |
| Iron Sulphate | FeSo4 |
| Lead Sulphate | PbSO4 |
| Copper Sulphate | CuSO4 |
| Mercury Sulphate | HgSO4 |
| Silver Sulphate | Ag2SO4 |
Nitrates
| Name Of Nitrate | Formula |
| Ammonium Nitrate | NH4NO3 |
| Sodium Nitrate | NaNO3 |
| Potassium Nitrate | KNO3 |
| Calcium Nitrate | Ca(NO3)2 |
| Magnesium Nitrate | Mg(NO3)2 |
| Aluminium Nitrate | Al(NO3)3 |
| Zinc Nitrate | Zn(NO3)2 |
| Iron Nitrate | Fe(NO3)2 |
| Lead Nitrate | Pb(NO3)2 |
| Copper Nitrate | Cu(NO3)2 |
| Mercury Nitrate | Hg(NO3)2 |
| Silver Nitrate | AgNO3 |
Chloride
| Name Of Chloride | Formula |
| Ammonium Chloride | NH4Cl |
| Sodium Chloride | NaCl |
| Potassium Chloride | KCl |
| Calcium Chloride | CaCl2 |
| Magnesium Chloride | MgCl2 |
| Aluminium Chloride | AlCl3 |
| Zinc Chloride | ZnCl2 |
| Iron Chloride | FeCl2 |
| Copper Chloride | CuCl2 |
| Silver Chloride | AgCl |
Oxides
| Name Of Oxide | Formula |
| Sodium oxide | Na2O |
| Potassium Oxide | K 2O |
| Magnesium Oxide | MgO |
| Calcium Oxide | CaO |
| Aluminium Oxide | Al2O3 |
| Zinc Oxide | ZnO |
| Iron Oxide | FeO |
| Lead Oxide | PbO |
| Copper Oxide | CuO |
| Mercury Oxide | HgO |
Hydroxides
Chemical Name | Formula |
| Ammonium Hydroxide | NH4OH |
| Sodium Hydroxide | NaOH |
| Potassium Hydroxide | KOH |
| Calcium Hydroxide | Ca(OH)2 |
| Magnesium Hydroxide | Mg(OH)2 |
| Aluminium Hydroxide | Al(OH)3 |
| Zinc Hydroxide | Zn(OH)2 |
Indicators
In chemistry, natural or synthetic substance that changes color in response to the nature of its chemical environment. Indicators are used to provide information about the degree of acidity of a substance (pH) or the state of some chemical reaction within a solution being tested or analyzed. One of the oldest indicators is litmus, a vegetable dye that turns red in acid solutions and blue in basic ones. Other indicators include alizarin, methyl red, and phenolphthalein, each one being useful for a particular range of acidity or a certain type of chemical reaction.
Litmus, vegetable dye obtained from lichens, usually of the genus Variolaria, and used in chemistry to determine the presence of acids and bases in a solution. Strips of paper impregnated with a blue or red litmus solution, or small quantities of the solution itself, are used to indicate the presence of an acid or a base; acids turn blue litmus red, and bases turn red litmus blue.
pH, term indicating the hydrogen ion (positively charged hydrogen atom) concentration of a solution, a measure of the solution’s acidity. Hydrogen ions are usually represented by the symbol H+. The term (from French pouvoir hydrogène, “hydrogen power”) is defined as the negative logarithm of the concentration of H+ ions: pH = -log10[H+], where [H+] is the concentration of H+ ions in moles per litre. Because H+ ions associate with water molecules to form hydronium (H3O+) ions, pH also is often expressed in terms of the concentration of hydronium ions.
Chemical Reaction
When one or more substances undergo a chemical change, with the absorption or release of energy, so as to form one or more new products, then the change taking place collectively is called chemical reaction.
In a chemical reaction, the substance(s) which take part in bringing about a chemical change are called reactants.
The substance(s) which are produced as a result of chemical change are called products.
Conditions for a chemical reaction
- There must be one or more substances to take part in a chemical reaction.
- There must be absorption or release of energy during a chemical reaction.
- At least one substance should be formed during a chemical reaction.
Some chemical reactions are characterised by the evolution of a gas. For eg. when baking soda( Sodium Hydrogen Carbonate - NaHCO3
NaHCO3 + CH3COOH
CH3COONa + H2O + CO2CH3COONa is Sodium Acetate.
Change of colour
Some chemical reactions are characterised by the change of colour of reactants. For eg. when copper carbonate( green colour - CuCO3) is heated strongly, it leaves behind a black residue of copper copper oxide( CuO) and gives off Carbon dioxide( CO2
CuCO3
CuO + CO2Formation of precipitate (ppt)
Some chemical reactions are characterised by the formation of a precipitate( an insoluble substance), when the solutions of two chemical compounds are mixed together. For eg. a white precipitate of silver chloride is formed when a colourless solution of silver nitrate is mixed with a colourless solution of sodium chloride. It can be represented as
AgNO3(Solution) + NaCl(Solution) NaNO3(Solution) + AgCl(White Precipitate)
Energy Changes
Some chemical reactions are characterised by the release or absorption of energy. For eg. when a small piece of quick lime(calcium oxide - CaO) is placed in about 100 cc of water, the water becomes very hot and sometimes start boiling. It is because, the calcium oxide(CaO) reacts with water to form calcium hydroxide with the release of heat energy. It can be represented as
CaO + H2O Ca(OH)2 + Heat Energy
Change of State
Some chemical reactions are characterised by the change of state. For eg. Ammonia gas(NH3 - Hydrogen Nitride) reacts with Hydrochloric acid(HCl - Hydrogen Chloride) gas to form dense white fumes of ammonium chloride(NH4Cl), which is in the solid state. It can be represented as
NH3 + HClSolid NH4ClTypes of Chemical Reactions
Chemical Combination/Composition - When two or more elements or compounds react chemically to form only one new product, then the reaction which takes place is called chemical combination.
Examples
When a mixture of iron fillings and sulphur is heated strongly, it reacts to form iron sulphide(FeS). It can be represented as
Fe + S
FeSWhen quicklime(CaO) is mixed with water, it reacts to form a single new product, calcium hydroxide(Ca(OH)2). It can be represented as
CaO + H2O
Ca(OH)2Note : Heat energy is also released during this reaction. Heat is an energy and so is not considered as a product.
Chemical Decomposition/Decombination - When a single chemical compound decomposes on heating or by some other kind of energy, so as to form two or more new substances, then the chemical reaction which takes place is called chemical decomposition.
Examples
Mercury oxide(HgO) on strong heating decomposes to form mercury(Hg) and oxygen(O). It can be represented as
HgO
Hg + OWhen marble chips(Calcium Carbonate - CaCO3) are heated strongly, they decompose to form Calcium Oxide(CaO) and Carbon Dioxide(CO2). It can be represented as
CaCO3
CaO + CO2Chemical Displacement/Replacement - When a more reactive element displaces a less reactive element from its aqueous salt solution(from its water solution), the reaction which takes place is known as chemical displacement.
There is a list of reactivity of common elements. It is given below in the order of decreasing reactivity.
Potassium > Sodium > Calcium > Magnesium > Aluminium > Zinc > Iron > Lead > Hydrogen > Copper > Mercury > Silver > Gold
In the above list Hydrogen a non metal is included. because the metals above hydrogen donot react with water or dilute sulphuric acid or dilute hydrochloric acid and hence do not displace hydrogen.
Examples
Iron(Fe), reacts with copper sulphate(CuSO4) solution to displace Copper(Cu - Because its less reactive than Iron) and forms a solution of iron sulphate(FeSO4).It can be represented as
Fe + CuSO4(Solution)
FeSO4 + Cu.Zinc(Zn) reacts with dilute Sulphuric Acid(H2SO4
Zn + H2SO4(Dilute)
ZnSO4 + HSalts
Salts- Water of Crystalization
On heating the hydrated salts lose their water molecules( water of crystallization). In doing so they lose their colour and shape and form a powdery substance. The compound left after heating is called anhydrous salt. Anhydrous regain the colour after the addition of water for eg. Copper Sulphate loses its blue colour after heating and regains its colour after addition of water.
The water of crystallization is always mentioned after a dot(.) for eg. Copper Sulphate is CuSO4.5H2O.
USES OF SALTS IN DAILY LIFE1. Common Salt [NaCl] : It is used as table salt. It is used for preservation of food in pickling. It is used to preserve raw hides. It is used in the manufacture of chemicals such as chlorine, caustic soda (NaOH) and washing soda (Na2CO3).
2. Baking Soda [NaHCO3] : It is used for making baking powder. It is used for preparing antacid tablets, for controlling acidity in the stomach.
3. Washing Soda [Na2CO3] : It is used by washermen to wash clothes. It is used in manufacture of glass and caustic soda. It is used in fire extinguishers. It is used in the manufacture of detergents.
4.
5. Nitre [KNO3] : It is used as a fertilizer. It is also used in the manufacture of gun powder, fire works and Nitric acid.
6. Smelling salt [(NH4)2CO3] : It provides relief from common cold.
7. Epsom Salt [MgSO4] : It is used as a laxative by patients suffering from constipation.
8. Green Vitriol [FeSO4.5H2O] : It is used in making blue – black inks and in curing leather.
9. Blue Vitriol [CuSO4.5H20] : It is used as fungicide in agriculture. It is used in dyeing and printing industry. It is used in electroplating copper metal.
10. Plaster of Paris [CaSO4.1/2H2O] : It is used for making statues. It is used for setting broken bones.
11. Potash alum [K2SO4.Al2(SO4)3.24H2O] : It helps in rapid settling of suspended impurities in water. It is used for the purification of water.
Hydrocarbons
Hydrocarbons are nothing but organic compounds consisting entirely of Hydrogen and Carbon. Hydrocarbons come under a different branch of Chemistry – Organic Chemistry.
Organic Chemistry – An Introduction
Carbon unites with many elements to form a great variety of compounds that are found in such substances as coal, petroleum, fabrics, plastics, and rubber. Other carbon compounds include plant and animal tissues, sugars, proteins, starches, and cellulose. About 1 million carbon compounds are known. The substances that contain carbon are called organic compounds, and the science that deals with them is known as organic chemistry.
This name arose because chemists once thought that many of these compounds could be formed only by a vital force (a life process). This was disproved in 1828 when the German chemist Friedrich Wöhler converted the compound ammonium cyanate, NH4CNO, into urea (NH2)2CO.
Before this, urea had been known only as a product of life processes. Today chemists can make many of the products that formerly had been produced only by living plants and animals.
Carbon compounds exist in such number and variety because of the chemical properties of carbon. Since carbon is in Group IV A of the periodic table, it appears to be midway between the metals and nonmetals and has the ability to react with both types of elements. The structure of the carbon atom is unique among atoms, allowing a great array of compounds that are stable under normal atmospheric conditions and reactive in other situations. Carbon reacts as follows:
1. Carbon atoms have the unusual property of combining with each other to form rings or long chains. No other element does so as extensively.
2. Carbon will combine with many different atoms or groups of atoms. This property, together with the ability to form long chains, makes carbon the most versatile of all elements in forming compounds.
3. Carbon forms many compounds that exist as isomers. Isomers are molecules with the same number and kinds of atoms, but in different arrangements.
Let’s get back to Hydrocarbons.
Hydrocarbons are one of the most important energy resources of the Earth. The main usage is as a combustible fuel source.
Hydrocarbons are currently the main source of the world’s electric energy and heat sources (such as home heating) because of the energy produced when burnt. Often this energy is used directly as heat such as in home heaters, which use either oil or natural gas. The hydrocarbon is burnt and the heat is used to heat water, which is then circulated. A similar principle is used to create electric energy in power plants.
As methane only releases one carbon dioxide for two water molecules, it is considered the cleanest fuel.
Liquid geologically-extracted hydrocarbons are referred to as petroleum (literally "rock oil") or mineral oil, while gaseous geologic hydrocarbons are referred to as natural gas. All are significant sources of fuel and raw materials as a feedstock for the production of organic chemicals and are commonly found in the Earth's subsurface using the tools of petroleum geology.
The extraction of liquid hydrocarbon fuel from a number of sedimentary basins has been integral to modern energy development. Hydrocarbons are mined from tar sands, oil shale and potentially extracted from sedimentary methane hydrates. These reserves require distillation and upgrading to produce synthetic crude and petroleum.
Oil reserves in sedimentary rocks are the principal source of hydrocarbons for the energy, transport and petrochemical industries. Hydrocarbons are of prime economic importance because they encompass the constituents of the major fossil fuels (coal, petroleum, natural gas, etc.) and plastics, paraffin, waxes, solvents and oils.
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