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Definitions and concepts for IGCSE chemistry:

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  Definitions and concepts for IGCSE chemistry: Acids bases and salts: 1. Acid : A chemical which can neutralize bases and will turn both litmus and methyl orange red. Acids will react with metals to produce salt and hydrogen and will react with carbonates to produce salt, water and carbon dioxide. Acids are proton donors. 2. Amphoteric : Able to act as an acid and a base. 3. Anion : A negatively charged ion formed when an atom gains at least one electron. 4. Base : A chemical which reacts with acids in neutralization reactions and will turn litmus blue and methyl orange yellow. Bases react with ammonium salts to produce salt, ammonia gas and water. Bases are proton acceptors. 5. Cation : A positively charged ion formed when an atom loses at least one electron. 6. Crystallization : A separation technique to soluble solids from solutions. The process involves heating the solution until crystals start to form, leaving the solution to cool and then filtering the formed crystals from ...

Carbon: An important element

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Allotropy -  some elements occur in nature more than one form. The chemical properties of these different forms are the same but their physical properties are different. This property of the elements is called allotropy.  Allotropes of carbon : The element carbon is available abundantly in nature and occurs in free as well as in a combined state.  1. Symbol of carbon-C 2. Atomic number -6 3. Atomic mass -12 4. Electron configuration- 2,4 5. Valency -4 6. Non-metallic element Compounds obtained directly or indirectly from plants and animals are called organic compounds and compounds obtained from minerals are called inorgani uuc compounds. All the organic compounds contain carbon. Carbon is the main element even in cellular DNA and RNA that transfer hidden characteristics from one generation to the next. Occurrence of carbon - The name carbon is derived from the Latin word 'carbo' meaning coal. Carbon is found in nature in a free as well as compound state carbo...

Metallurgy, properties of metals

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Source: Internet Earth was born about 4.5 billion years ago. Various formative processes have been taking in the core of the earth and it's surroundings  since its creation today. These have resulted in the formation of various ores, liquids and gases.  Physical properties of metals: Metal exist mainly in solid state. The metals namely, Mercury and gallium exist in liquid state at room temperature. Metals posses luster. The metallic luster goes on decreasing due to exposure to atmospheric oxygen and moisture and also in presence of some reactive gases. We know that metals have the properties namely, ductility and malleability. Similarly, all metals are good conductors of heat and electricity. Generally, all metals are hard. However, the alkali metal from group 1 such as lithium, sodium and potassium are exceptions. These metals can be cut with knife as they are very soft. Metals have high melting and boiling points. For example, tungsten metal has the highest melting point (3...

What is Polymer? How they are classified?

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 Introduction: Polymers are macromolecules having high molecular weights and are composed of smaller repeating units called monomers.  The term polymer is derived from the Greek root 'poly' means 'many' and 'meros' means 'parts'.  Monomers are small and simple molecules and have the capacity of forming two chemical bonds with two other monomers. The functionality of monomers depends upon the number of bonding sites in monomers.  DNA in a human body, proteins, muscles, nerve fibers, nails, hairs, etc. are all polymers. Carbohydrates have important functions in biological systems. The toys of our children are plastic polymers. Classification: There are various ways to classify polymers based on source, structure, mode of forming, molecular forces, etc. classification based on source: Polymers are classified into three subclasses as given below, Natural polymers: These polymers are obtained either from plants or animals and are named plant polymers and anim...

What is analytical chemistry? What are the applications of it?

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Analytical chemistry: Analytical chemistry studies and uses instruments and methods used to separate, identify and quantify matter in practice separation identification for qualification main constituent the entire analysis or be combined with another method. Separations isolates analytes. Qualitative analysis identifies analytes, while quantitative analysis determine the numerical amount or concentration. Analytical chemistry involves the following methods: The process of separation isolates the required chemical species which is to be analysed from a mixture. The concentration of the analyte in a given mixture can be determined with the method of quantitative analysis. The identification of the analyte substance is achieved via the method of qualitative analysis. The methods used to determine the identity and the quantity of the analytical chemistry can be broadly divided into classical and instrumental methods. 1.Classical methods: There exist many classical methods of checking for ...

Chemistry of Water, structure of water

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Water : Water is a chemical compound consisting of two hydrogen atoms and one oxygen atom. The name water typically refers to the liquid state of the compound. The solid phase is known as ice and the gas phase is called steam. Under certain conditions, water also forms a supercritical fluid. source: Internet   Chemical properties of water: In chemistry, positive and negative electrical charges attract each other, like charges repel each other. The negative ends of dipolar water molecules are attracted to molecules and atoms with positive charges, and vice versa. In liquid water, there is some self dissociation giving hydronium ions & hydroxide ions. Pure water is flavorlees and odourless. Water is the main compound found in living organisms. Approximately 62 percent of the human body is water. Surface Tension, Heat of vapor Pressure. The viscosity of cohesion. Solid-state. Liquid state. Gas state. Boiling Point and freezing point. Why water is important to CHEMISTRY? More impor...

The short description of chemistry of carbon compounds

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  Chemistry of carbon compound: Carbon plays a very important role for all living beings. The presence of carbon in the atmosphere of the earth is 0.03% in the form of carbon dioxide. The amount of carbon in the earth's crust is merely 0.02% which is available in the form of minerals such as carbonates, coal, and petroleum. Compounds of Carbon: Almost all carbon compounds (except a few) are poor conductors of electricity. The diamond and graphite both  are formed by carbon atoms; however,  the difference lies between them in the manner in which the carbon atoms are bonded to one another. In a diamond, each atom of the carbon is bonded to four other carbon atoms and forms a rigid 3-dimensional structure.  In graphite, each atom of the carbon is bonded to three other carbon atoms in the same plane, which gives a hexagonal array. There is a difference in some physical structures of diamond and graphite. Diamond is the hardest substance known whereas graphite is a smooth...

The basics concept of chemistry | What is Atom? Characteristics of atoms? What are the types of chemical bond?

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CHEMISTRY is the science and study of matter, including its properties, composition as well as reactivity. Chemistry relates to everything that can be sensed from the minutes elements to complex structures. The atom and molecules are the Basic units or components of chemistry. Atom: All matter consists of particles known as an atom. Atoms bond to each other to form elements, which contain only one kind of atom. Atoms of different elements form compounds, molecules, and objects. Model of the atom: An atom is a building block of matter that can not be broken apart using any chemical means. The 3 parts of the atoms are protons (positively charged), neutrons (neutral charged), and electrons (negatively charged). Proton and neutron form the NUCLEUS . Electrons are attracted to the protons in the nucleus but are moving quickly they fall toward orbit rather than stick to protons. The identity of an atom is determined by it's no. of protons. This is also called its atomic number. PARTS OF ...

Organic chemistry

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Q.What is Organic chemistry? Ans: Organic chemistry is the study of the structure, properties, composition, reactions, and preparation of carbon containing compounds, which including hydrocarbons but also compounds with any number of element, including hydrogen, nitrogen, oxygen, halogens, etc. About Carbon - In their outer shells, carbon atom have four electrons that can bond with other atoms. When carbon is bonded to to hydrogen, the carbon atom shares an electron with hydrogen and hydrogen likewise shares an electron with carbon. The compound containing carbon and hydrogen known as hydrocarbons. Tetravalency of carbon- The atomic number of carbon is 6 and its electronic configuration is 2,4 i.e it has 4 valence electrons. Thus carbon is always tetracovalent i.e it forms 4 covalent bonds with other atoms. Due to tetravalency of carbon it has a tetrahedron shape. Catenation - The self linking property of carbon is known as catenation. This is the main reason of existence of such larg...

Chemistry in Kitchen |What is the ROLE of CHEMISTRY in the Kitchen?

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The experiments in Kitchen chemistry sets go beyond the ratio of ingredients, incorporating acid/ base reactions (like baking soda and vinegar), the effects of heat, states of matter, crystal formation, and other principles. One common experiment is making rock candy, which is simply a colored crystal formed from sugar molecules crystallizing out of a supersaturated sugar solution. This effect is achieved by dissolving sugar in warm water until the solution is saturated. (meaning no more sugar can dissolve) As the mixture cools, a single crystal causes a chain reaction that transforms the entire solution into solid crystal. What chemicals are used in the kitchen? Here are some chemicals in the kitchen used for cleaning.  1. Ammonia  2. Sodium hypo chloride  3. Chlorine  4. Carbon  5. Sulphuric acid  What is the ROLE of CHEMISTRY in the Kitchen?  The role of chemistry in the kitchen is highly significant. We can interpret almost all the activities of th...