what is chemical and what is chemical reaction

BASICS OF CHEMISTRY

Chemical-any substance that has a defined composition

Chemical reaction- the process by which one or more substances change to produce one or more different substances

States of matter-the physical forms of matters, which are solid, liquid, gas, and plasma 

Reactant- a substance or molecule that participates in a chemical reaction  Product- a substance that forms in a chemical reaction

Matter-anything that has mass and takes up space
Volume-a measure of the size of a body or region in three-dimensional space
Mass-a measure of the amount of matter in an object; a fundamental property of an object that is not affected by the forces that act on the object, such as the gravitational force
Weight- a measure of the gravitational force exerted on an object; its value can change with the location of the object in the universe
Quantity- something that has magnitude, size, or amount
Unit- a quantity adopted as a standard of measurement
Conversion Factor- a ration that is derived form the equality of two different units that can be used to convert from one unit to the other
Physical property- a characteristic of a substance that does not involve a chemical change, such as density, color, or hardness
Density –the ratio of the mass of a substance to the volume of the substance; often expressed as grams per cubic centimeter for solids and liquids and as grams per liter for gases
Chemical Property- a property of matter that describes a substance’s ability to participate in chemical reactions
Atom- the smallest unit of an element that maintains the properties of that element
Pure Substance- a sample of matter, either a single element or compound, that has definite chemical and physical properties
Element- a substance that cannot be separated or broken down into simpler substances by chemical means’ all atoms of an element have the same atomic number
Molecule- the smallest unit of a substance that keeps all of the physical and chemical properties of that substance; it can consist of one atom or two or more atoms bonded together
Compound- a substance made up of atoms of two or more different elements joined by chemical bonds
Mixture- a combination of two or more substances that are not chemically combined
Homogeneous- describes something that has a uniform structure or composition throughout
Heterogeneous- composed of dissimilar components

by: Chemistry Notes Info www.ChemistryNotesInfo.Blogspot.Com

Chemical Reactions and Chemical Formula

Chemical Reactions

Chemical Reaction is the reaction in which two or more than two substances react to form a new substance is known as Chemical Reaction. The substances which react may be ion or compound of element.

Reaction: Reactant reacts with each other to give product.

               Reactant   -------->  Product

Example of general chemical reactions from daily life is rusting of iron, formation of curd from milk etc.

Chemical Formula

                               Chemical Formula is simple representation of any compound by writing together the numbers and symbols of constituting elements forming that compound.

Example: H₂O, CaCl₂, AlCl₃, Ca(OH)₂

Chemical Formula for Ionic Compounds

                                                     As we know Ionic compound formed as a result of electron transfer between metal and non-metal atoms. When we have to write chemical formula for ionic compound then write metal atom symbol on left hand side and non-metal atom symbol on right hand side. Metal atom name remain same but ‘ide’ or ‘ate’suffix is added to non-metal atom name.

Ionic compound formed by one metal atom and non-metal atoms.

Metal Atom		Non-Metal Atom		Name of Compound	Chemical Formula  of Compound
Name and Symbol	No.	Name and Symbol	No.
Calcium (Ca)	1	Oxygen (O)	1	Calcium Oxide	CaO
Magnesium (Mg)	1	Chlorine (Cl)	2	Magnesium Chloride	MgCl2
Aluminium (Al)	1	Chlorine (Cl)	3	Aluminium Chloride	AlCl3

    Chemical Formula for Covalent Compounds

                                                                        As we know covalent compound formed as a result of electron sharing and contains non-metal atoms. When we have to write chemical formula for covalent compound then relatively less electronegative non-metal atom symbol is written on left hand side and other witch is more electronegative is written  on right hand side. Name of non-metal atom which is written on left hand side is remain same but ‘ide’ suffix is added to non-metal atom name which is written on right hand side. 

Covalent compound formed by two  non-metal atoms.

Low Electronegative Non-Metal Atom		High Electronegative Non-Metal Atom		Chemical Name of Compound	Chemical Formula  of Compound
Name and Symbol	No.	Name and Symbol	No.
Carbon (C)	1	Oxygen (O)	1	Carbon Mono Oxide	CO
Carbon (C)	1	Oxygen (O)	2	Carbon Di Oxide	CO2
Phosphorus (P)	1	Chlorine (Cl)	3	Phosphorus Tri Chloride	PCl3
Phosphorus (P)	1	Chlorine (Cl)	5	Phosphorus Penta Chloride	PCl5
Nitrogen (N)	2	Oxygen (O)	5	Nitrogen Penta Oxide	N2O5

Important Chemistry Polymers with their Monomer, Formula and Uses

Important Polymer Table

Important Polymers with their Monomer, Formula and Uses.

Polymers	Monomers	Monomer Formula	Use
1.    Teflon	Tetrafluroethene	CF2=CF2	Oil seals, Gasket
2.    Polyacrylonitrile	Acrylonitrile		Commercial Fibers
3.    Terylene or Decron	Ethylene Glycol Teryphthalic Acid	HOCH2-CH2OH	Commercial Fibers
4.    Nylon 6,6 And 5.    Nylon 6	Hexamethylene-diamine Adipic Acid Caprolactum	NH2(CH2)6NH2 HOOC(CH2)4COOH	Making Sheets, bristles of brushes, textile industry, tyre cords, fabrics, ropes etc.
6.    Phenol Formaldehyde Polymer
i.                   Novolac	Phenol + Formaldehyde	HCHO	Used in paints
ii.                 Bakelite	Phenol + Formaldehyde	HCHO	Comb, Electric switches
7.    Malamine Formaldehyde Polymer	Malamine + Formaldehyde	HCHO	Unbreakable crockery
8.    Buna S	1,3-Butadiene + Styrene	CH2=CH-CH=CH2	Auto tyres, cables insulation, floor tiles

Lower Density Polyethene  (L.D.P.) : Lower Density Polythene are prepared at 1000-2000 atm pressure, 350-570 Kelvin Temperature and O₂ peroxide inhibitor.

Higher Density Polyethene  (H.D.P.) : High Density Polythene are prepared at 6-7 atm pressure, 333-343 Kelvin Temperature and Zieglar Natta Catalyst.

Posted by "Jitendra Singh Sandhu" at "Chemistry Notes Info"

Types of Chemical Reactions

Types of Chemical Reactions

Chemical reactions are reactions which involve making and breaking of bonds between atom to yield new substances.

    1.    Combination Reaction:

These are the reactions in which one single product is formed from two or more reactants.

Example: i. Formation of Calcium Hydroxide.

CaO (s)(quick lime) + H₂O (l) ----> Ca(OH)₂ (aq)(slaked lime)

ii. Burning of Coal.

C (s) + O₂ (g) ----> CO₂ (g)

iii. Formation of Water.

2H₂ (g) + O₂ (g) ----> 2H₂O (l)

    2.    Displacement Reaction:

These are the reactions in which highly reactive metal displaces less reactive metal from their solution.

Example: i. Fe (s) + CuSO₄ (aq)(copper sulphate) ----> FeSO₄ (aq)(iron sulphate) + Cu (s)

 ii. Zn (s) + CuSO₄ (aq)(copper sulphate) ------> ZnSO₄ (aq)(zinc sulphate) + Cu (s)

iii. Pb (s) + CuCl₂ (aq)(copper chloride) ------> PbCl₂ (aq)(lead chloride) + Cu (s)

    3.    Double Displacement Reaction:

These are the reactions in which exchange of ions between reactants occur.

Example: Na­₂SO₄ (aq)(sodium sulphate) + BaCl₂ (aq)(barium chloride) -----> BaSO₄ (s)(barium sulphate) + 2NaCl (aq)(sodium chloride)

    4.    Oxidation and Reduction Reaction:

1.1.        Oxidation:

These are the reactions in which a substance loses hydrogen or gain oxygen.

          Example: 2Cu + O₂ + Heat ---------> 2CuO

1.2.        Reduction:

These are the reactions in which a substance gain hydrogen or loses oxygen.

          Example: CuO + H₂ + Heat -------> Cu + H₂O

1.3.        Redox Reaction:

These are the reactions in which one reactant gets reduced while other reactant gets oxidized. This type of reaction is also known as Oxidation-Reduction Reaction or Redox Reaction.

Example:

i.                   CuO + H₂ + Heat ------> Cu + H₂O

In above reaction-

                   H₂ ------> H₂O (oxidation)

                   CuO -----> Cu (reduction)

ii.                ZnO + C ------>  Zn + CO

iii.             MnO₂ + 4HCl ------> MnCl₂ + 2H₂O + Cl₂

Observable Effect of Oxidation Reduction in Everyday Life:

1.    Corrosion:

   Attack on metals by moisture, acids, oxygen etc., which corrode metals is called corrosion.

Example: Rusting of Iron, Black coating on Silver, Green coating on Copper.

2.    Rancidity:

   Change in taste and smell of food material prepared by using fat or oil, because fat or oil get oxidized and become rancid.

Endothermic Reaction:

                                      These are the reactions in which heat is absorbed during reaction.

Example: NH₄Cl (s) + H₂O (l) + Heat -                    -------> NH₄Cl (aq)

Exothermic Reaction:

                                      These are the reactions in which heat is evolved during reaction.

Example: CH₄ (g) + 2O₂ (g) -----> CO₂ (g) + 2H₂O (g) + Heat

Precipitation Reaction:

                                      These are the reactions in which insoluble substance called precipitate is obtained when reaction completes, is known as precipitation reaction.

Example: Na₂SO₄ (aq) + BaCl₂ (aq) ----> BaSO₄ (s) + 2NaCl (aq)

 

 

Chemical Reactions Quiz

1. Chemical Reaction, 2H₂O → 2H₂ + O₂ is a-

Synthesis Reaction
Decomposition Reaction
Combustion Reaction
Single Displacement Reaction
Double Displacement Reaction