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When chloroform reacts with nitric acid, nitrochloroform (chloropicrin) and water are formed. Nitration: The hydrogen of the chloroform is replaced by nitro group when it is treated with concentrated nitric acid. The product formed is chloropicrin or trichloronitro methane or nitro chloroform. It is a liquid, poisonous and used as an insecticide and a war gas.   CHCI3 + HONO2    ————→      CNO2 CI3  +  H2O                                      Nitric acid                    Chloropicrin (Tear gas)  Chloropicrin, also known as PS, is a chemical compound currently used as a broad-spectrum antimicrobial, fungicide, herbicide, insecticide, and nematicide. Its chemical structural formula is Cl3CNO2. In agriculture, chloropicrin is injected into soil prior to planting a crop in order to clean the soil of a broad spectrum of fungi, microbes, insects, and other harmful pests. It is commonly used as a stand alone treatment or in combination / co-formulation with methyl bromide and 1,3-Dichloropropene. Mr. Lalit Sardana(IIT-JEE AIR 243) is going to more...

Alkylation of ammonia The reaction of ammonia with an alkyl halide leads to the formation of a primary amine. The primary amine that is formed can also react with the alkyl halide, which leads to a disubstituted amine that can further react to form a trisubstituted amine. Therefore, the alkylation of ammonia leads to a mixture of products.    Mr. Lalit Sardana(IIT-JEE AIR 243) is an IIT-JEE tutor at Sardana Tutorials and he has been bringing up a number of IIT-JEE selections from the city. Many of the students are from Sardana tutorials itself. He owes a million of thanks from his students, as he gave them the strength, to make their dreams come true!.....This video is helpful to the students of 11th CBSE, 12th CBSE, JEE Mains, JEE Advanced, VITEEE, AIPMT, WBJEE, AFMC.   Watch the video now on this link http://www.studyadda.com/videos/jee-chemistry-lectures/amines/preparation-of-mixture-of-amines/1436 If you have more...

Amines are organic compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are derivatives of ammonia, wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group. Important amines include amino acids, biogenic amines, trimethylamine, and aniline. Inorganic derivatives of ammonia are also called amines, such as chloramine (NClH2); Compounds with the nitrogen atom attached to a carbonyl of the structure R–CO–NR′R″ are called amides and have different chemical properties from amines. An aliphatic amine has no aromatic ring attached directly to the nitrogen atom. Aromatic amines have the nitrogen atom connected to an aromatic ring as in the various anilines. The aromatic ring decreases the alkalinity of the amine, depending on its substituents. The presence of an amine group strongly increases the reactivity of the aromatic ring, due to an electron-donating effect. Amines are organized more...

Carbon tetrachloride, also known by many other names (the most notable being carbon tet in the cleaning industry, and as Halon 104 or Freon 10 in HVAC), is the organic compound with the formula CCl4. It was formerly widely used in fire extinguishers, as a precursor to refrigerants, and as a cleaning agent. It is a colourless liquid with a "sweet" smell that can be detected at low levels. Both carbon tetrachloride and tetrachloromethane are acceptable names under IUPAC nomenclature. Carbon tetrachloride was originally synthesised by the French chemist Henri Victor Regnault in 1839 by the reaction of chloroform with chlorine, but now it is mainly produced from methane: CH4 + 4 Cl2 → CCl4 + 4 HCl The production often utilizes by-products of other chlorination reactions, such as from the syntheses of dichloromethane and chloroform. Higher chlorocarbons are also subjected to "chlorinolysis:" C2Cl6 + Cl2 → 2 CCl4 Prior more...

Chloroform reacts with oxygen in the air to form phosgene (COCl2), a poisonous gas, according to the equation: 2CHCl3 + O2 ---> 2COCl2 + 2HCl In order to prevent this oxidation, ethanol or methanol should be added if you were planning to store it for an extended period of time. You should ensure that the chloroform contains 1-2% ethanol. Ethyl carbonate is produced and is harmless. COCl2 + 2CH3CH2OH ---> (C2H5O)2CO + 2HCl Phosgene is the chemical compound with the formula COCl2. This colorless gas gained infamy as a chemical weapon during World War I.  It is also a valued industrial reagent and building block in synthesis of pharmaceuticals and other organic compounds. In low concentrations, its odor resembles freshly cut hay or grass. In addition to its industrial production, small amounts occur naturally from the breakdown and the combustion of organochlorine compounds, such as those used in refrigeration systems. more...

VACCINATION Vaccination is the administration of antigenic material (a vaccine) to stimulate an individual's immune system to develop adaptive immunity to a pathogen. Vaccines can prevent or ameliorate morbidity from infection. The effectiveness of vaccination has been widely studied and verified; for example, the influenza vaccine,the HPV vaccine,and the chicken pox vaccine.Vaccination is the most effective method of preventing infectious diseases;widespread immunity due to vaccination is largely responsible for the worldwide eradication of smallpox and the restriction of diseases such as polio,measles, and tetanus from much of the world. The active agent of a vaccine may be intact but inactivated (non-infective) or attenuated (with reduced infectivity) forms of the causative pathogens, or purified components of the pathogen that have been found to be highly immunogenic (e.g., outer coat proteins of a virus). Toxoids are produced for immunization against toxin-based diseases, such as the modification of tetanospasmin toxin of tetanusto remove its toxic more...

Combinations of ResistorsResistors do not occur in isolation.  They are almost always part of a larger circuit, and frequently that larger circuit contains many resistors. It is often the case that resistors occur in combinations that repeat.Goals  Series Combinations of Resistors : Two elements are said to be in series whenever the same current physically flows through both of the elements. The critical point is that the same current flows through both resistors when two are in series.  The particular configuration does not matter.  The only thing that matters is that exactly the same current flows through both resistors.  Current flows into one element, through the element, out of the element into the other element, through the second element and out of the second element.  No part of the current that flows through one resistor "escapes" and none is added.  This figure shows several different ways that two resistors in more...

7 Ways to Prevent the Spread of Infection  1. Wash Your Hands!                           2. Clean and Disinfect!            3. Handle Food Safely            4. Get Immunized!           5. Don’t over-use antibiotics!         6. Keep Pets Healthy         7. Stay Away From Wild Animals! more...

Non Communicable Diseases  A non-communicable disease, or NCD, is a medical condition or disease, which by definition is non-infectious and non-transmissible among people. NCDs may be chronic diseases of long duration and slow progression, or they may result in more rapid death such as some types of sudden stroke. They include autoimmune diseases, heart disease, stroke, many  cancers, asthma,diabetes,  chronic  kidney disease, osteoporosis,Alzheimer's disease, cataracts, and more. While sometimes (incorrectly) referred to as synonymous with chronic diseases, NCDs are distinguished only by their non-infectious cause, not necessarily by their duration. Some chronic diseases of long duration, such as HIV/AIDS, are caused by transmittable infections. Chronic diseases require chronic care management as do all diseases that are slow to develop and of long duration. You will get friendly to this topic by clicking http://www.studyadda.com/videos/ix-class-biology-lectures/why-do-we-fall-ill/non-communicable-disease/1765Video Lecture Taught By-  Mrs. Shweta Sardana, Msc.,M.Phil Gold Medalist , AIPMT TrainerSardana Tutorials ï»¿ï»¿

 Modes of transmission OR Means Of Spread Of Communicable Diseases:Once an infectious agent leaves a reservoir, it must get transmitted to a new host if it is to multiply and cause disease. The route by which an infectious agent is transmitted from a reservoir to another host is called the mode of transmission. It is important for you to identify different modes of transmission, because prevention and control measures differ depending on the type. Direct modes of transmission Direct transmission refers to the transfer of an infectious agent from an infected host to a new host, without the need for intermediates such as air, food, water or other animals. Direct modes of transmission can occur in two main ways:

• Person to person: The infectious agent is spread by direct contact between people through touching, biting, kissing, sexual intercourse or direct projection of respiratory droplets into another person’s nose more...