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General Knowledge for Competitive Exams

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Do you know why Oil and Water does not mix together?

Nov 17, 2017
We have seen many times and even we have tried at our homes that when we put oil in water and stir it, eventually they separate in to two distinct layers. Why is it so? Through this article we will study why oil and water does not mix together, why oil is sticky and why oil floats on water.

What is SMOG and how it is harmful for us?

Nov 8, 2017
Smog is derived from two words i.e. smoke and fog which is also described as a mixture of various gases with dust and water vapour and makes breathing difficult. In 17 years such an alarming situation raised in Delhi which raised health emergency. In this article we will discuss about the sources of smog, how it affects our health and how it is formed; what are the necessary precautions that we can take etc.

What is the role of Helium in Medicines?

Nov 6, 2017
Helium is the lightest noble gas. It consists of various physical and chemical properties due to which it is used in respiratory ailments therapies. Due to its inert gas property it helps in neuroprotection, in surgery, in MRI technique etc. This article deals with the role of helium in medicines and how it is used in various techniques for the treatment of patients.

Is Nitrogen important for Human Body?

Nov 1, 2017
Nitrogen is represented by the symbol N. It is abundant in the environment but humans can’t use it directly from air or soil but depends upon green plants and microbes to convert it in to the usable form for using it. But the question arises that why Nitrogen is important for humans and how they use it etc. are discussed in this article.

What is the function of hydrogen in the human body?

Oct 26, 2017
Hydrogen is the first element of the periodic table. The most important function of hydrogen in the human body is to keep you hydrated. Water is made up of hydrogen and oxygen and is absorbed by the cells of the body. Therefore, it is a crucial element which is used not in our body but also as a fuel, in military weapons etc. This article deals with the importance and function of hydrogen in the human body.

Which acid is used to peel ginger skin and how it affects health?

Oct 7, 2017
Ginger is a very common spice which is used in almost everyone's homes for cooking. But adulteration of ginger is a life threatening issue which is causing several serious diseases like cancer. Which acid is used by the vegetable vendors to make ginger shiny or polished and how it can affect health is discussed in this article.

What are Generic Medicines and why are they affordable

Oct 5, 2017
According to the World Health Organization, if doctor started prescribing generic medicines, then health expenditure can be reduced by 70% in developed countries and developing countries. Generic drugs consumption is only 10-12 percent of the total drug market. Greedy attitude of the drug manufacturer companies, medical stores and doctors don't want to spread the market of generic drugs. In today’s world almost all type of generic drugs are available at the price lower than the branded medicines.

What is the reason behind floating ice on water

Sep 15, 2017
Have you ever thought! How any solid object floats on any fluid? Solids are hard and rigid like stones. They immersed in water, but the ice, which is a solid substance, does not sink in water, but floats. Why? Let us find out why ice being a solid substance floats on water.

Is Nitrogen drink dangerous for health

Sep 12, 2017
Liquid Nitrogen is a fluid that is used in foods such as drinks, ice creams, etc. Nitrogen drinks look great and appeal everyone, but how to use it, try to figure out how much damage it may cause, Is it safe to drink or not etc are discussed in this article.

List of some common man-made Polymers and their Uses

Dec 23, 2016
Polymers are made up of various molecules which combine together to form long chains. They usually have high melting and boiling points like PVC (poly vinyl chloride), polystyrene, cellulose. Therefore, the list of polymers with their uses is helpful in the academic and competitive exam preparations.

Important facts about Metals

Dec 23, 2016
Metals are the elements which form positive ions by losing electrons or donate electrons. Metals are also known as electropositive elements as they form positive ions on losing electrons. In this article we will see some important facts about metals which will be helpful in various exams preparations.

List of Important Metals and their Ores

Dec 21, 2016
Metals are the element that loses electrons easily and have positive ions or cations. It consists of metallic bonds. In this article we will see what are metals, ores, its properties, etc. Also, a list of important metals with ores is given which will give an idea of metals and from where they are extracted and help with your various exam preparations through which you will be able to learn the formulas of elements.

List of Important Alloys and their Uses

Dec 20, 2016
Alloy plays a very important role in our daily life. Utensils in the kitchen, vehicles, mobile phones etc are various alloys which are being used and made by human. Here, we are providing the list of important alloys and their uses which will help in revising at the time of examination.

List of the Important Salts and their Uses

Oct 13, 2016
A salt is compound that formed from an acid by the replacement of the hydrogen in the acid by a metal. They are formed when acids reacts with base. Lets us find out the list of various salts and their uses which may be helpful for competetive examinations.

“General Science” A Complete Study Material

Jun 6, 2016
The Complete Study Material of “General Science” i.e. Physics, Chemistry and Biology is given in a compiled form that will be very helpful for the students of 6th to 12th class, undergraduates and those who are preparing for competitive exams familiar with the diversity of the subject and make them understand the concepts.

What is Catalysis?

Mar 11, 2016
The chemical substance due to the presence of which rate of chemical reaction is increased or decreased but does not take part in chemical reaction itself is called catalyst and the process is called catalysis. Jons Jacob Berzelius discovered the chemical phenomena of catalysis in 1835 and he confirmed that the rate of reaction can be affected by the presence of any chemical substance.

List of important Synthetic fibres

Mar 11, 2016
Fibres are the solid substance which has long chained structure and whose length is much larger than its breadth is called fibres. These are the polymers of so many simple molecules which are composed and combined in laboratories. The synthetic substances Rayon, Nylon, Polyester etc are the examples of synthetic fibres.

Chemical Explosives: Highly reactive substance after combustion

Mar 11, 2016
Explosives are those substance which provides extreme heat and energy and a sharp cracking sound on combustion. They usually have less potential energy than fuels, but their high rate of energy produces a great blast pressure.For a chemical to be an explosive, it must exhibit all of the following: Rapid expansion (i.e., rapid production of gases or rapid heating of surroundings);evolution of heat;rapidity of reaction; and initiation of reaction.

Alcoholic Beverages: Types and uses

Mar 8, 2016
Wine is an alcoholic beverage which is prepared by the composition of various fermented substances and the amount of alcohol is different in different types of wine. There are various types of 'wine like beer, champagne, cider, port and sherry, whisky, Rum, Brandy, and Gin etc. Also in the beer the amount of alcohol is extremely low, while in the Rum this amount is extremely high and the champagne is the most costly wine among all.

Glass: Composition, types and uses

Mar 3, 2016
Glass is a non-crystalline amorphous solid that is often transparent and has widespread practical, technological, and decorative usage in, for example, window panes, tableware, and optoelectronics. Firstly the glass was manufactured in Egypt. Ordinary glass is manufactured by the composition of various substances like silica, bleaching powder, oxides of alkaline metals, calcium oxide (lime) etc.

List of important Drugs and Chemicals

Mar 1, 2016
Drugs (medicines) are something that treats, prevents or alleviates the symptoms of disease. Two things make a drug important: Firstly, it is used to treat a large number of people with a range of health problems and; secondly, these drugs spurred the pharmaceutical industry to further research and innovation. It is manufactured or produce not only through the extraction of medicinal plant like aloe Vera, tulsi plant, garlic etc. but also through organic synthesis.

Hydrocarbon: Types and Importance

Mar 1, 2016
Hydrocarbons are the Organic compounds obtained by the simple combination of hydrogen and carbon like petrol, diesel, and kerosene oil etc. It is usually divided into two categories: Aliphatic hydrocarbon; Aromatic hydrocarbon.

Fertilizer: Types and important fertilizers

Mar 1, 2016
A fertilizer or fertiliser is that substance which is used to make soil more fertile such as manure or a mixture of nitrates. It is applied to the soils or to plant tissues (usually leaves) to supply one or more plant nutrients essential to the growth of plants. Hence, we can say in other words that the fertilizers are the chemical substances which are directly respondent for the substantial growth of the plants (trees) or crops and being supply the nutrients in the form of nitrogen, phosphorus, potassium etc and keep the soils fertile.

Salt: Concept, properties and uses

Mar 1, 2016
Salt is an ionic compound that results from the neutralization reaction of an acid and a base.It is composed of related numbers of cations (positively charged ions) and anions (negative ions) so that the product is electrically neutral (without a net charge). They may be simple salts such as NaCl, KCl, and Na2SO4; acid salts like NaHCO3 and NaH2PO4; or double salts like KAl (SO4)2.

Fundamentals of Inorganic Chemistry

Feb 26, 2016
Inorganic chemistry is that chemistry which studied the synthesis and behaviour of inorganic and organ metallic compounds except the myriad organic compounds (carbon based compounds, usually containing C-H bonds).

Acids: Concept, properties and uses

Feb 26, 2016
Acid is a water-soluble compounds having a sour taste and capable of turning litmus red and reacting with a base to form a salt. In other word, it is a compound which contains replaceable hydrogen atom or atoms, a part or whole of which can be replaced by means of a metal or a positive radical. For Example: HCl, HNO3, H2SO4 etc are acids because they contain replaceable hydrogen atom or atoms.

List of important Organic Compounds

Feb 24, 2016
An organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon. Organic molecules are used by human in number of ways; it is used in industries like foods, pharmaceuticals, fuels etc. Alkanes consist of chemicals like propane, octane, and methane. These are used extensively as fuels for things like automobile gasoline and home heating/cooking fuel.

Formation of Substances

Feb 24, 2016
The substances that exist in the universe are made up of atoms (consists charge particles electron and proton)/molecules (made up of atom s)/ions). Chemical bonding is the binding force of the constituents’ atoms of the molecule to maintain a mutual atomic order and a definite but specific geometric shape. There are three types of chemical bonding – Electrovalent or Ionic, Covalent bonding and Co-ordinate covalent bonding.

The Concept and importance of pH Scale

Feb 24, 2016
S.P.L Sorenson, a Danish biochemist in 1909 devised a scale known as pH to represents the H+ ion concentration of an aqueous solution. The pH value of any solution is a number which simply represents the acidity and basicity of that solution. The pH value of any solution is numerically equal to the logarithm of the inverse of the hydrogen ion (H+) concentration. Hence, the pH of solution is referred to as the negative logarithm of hydrogen ion.

What is Galvanic Cells and how it work?

Feb 23, 2016
The Galvanic Cells is a device that transforms chemical energy into electric energy. It is the common application of electro chemistry which is also called battery. It was invented by Luigi Galvani and Alessandro Volta which has capability of producing a voltage. It has two conductive electrodes, called the anode and the cathode. The anode is an electrode where oxidation occurs. The cathode is an electrode where reduction takes place.

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