called atoms which cannot be created‚ destroyed or split b) all atoms of one element are identical:- same mass and same chemical properties c) a chemical reaction consists of rearranging atoms from one combination to another. d) When elements combine to form compounds‚ small whole numbers of atoms form molecules. However this was proved to be not entirely correct. Atoms have been split as well as created i.e. nuclear reactions. Also there are isotopes‚ meaning that not all atoms of an element
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a theoretical condition concerning a system at zero Kelvin where asystem does not emit or absorb energy (all atoms are at rest) accuracy - how close a value is to the actual or true value; also see precision acid - a compound that‚ when dissolved in water‚ gives a pH of less than 7.0 or a compound that donates a hydrogen ion acid anhydride - a compound with two acyl groups bound to a single oxygen atom acid dissociation constant - an equilibrium constant for the dissociation of a weak acid actinides -
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between nucleus and Ve-‚ stronger the metallic bonding 3) Physical properties Malleable and ductile The layer of cations can slide over each other without breaking the bond. Q: Why alloys are less malleable and ductile? A: Different sizes of atoms are introduced and less easy for cations to slide. Good conductor of electricity and heat Delocalized electrons are free to move from one side of lattice to the other. Luster Interaction between delocalized electrons and light Melting Point
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means that Silicon (Si) which has an atomic mass of 28.055 has 1 atom‚ equaling 16.306% mass percent. Calcium (Ca) has 40.078 atomic mass‚ which means there is 2 atoms at a 46.538% mass. Oxygen (O) has 15.99994 atomic mass‚ which means there are 4 atoms at 37.156% mass. In chemistry‚ this formula weight is a quantity computed from multiplying the atomic weight of units by each element in the chemical formula by the number of atoms which are present in the formula. Finding molar mass starts with
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Chem 3418 Organic Chemistry Laboratory I Acid Base Review Definition In general‚ an acid is a substance that can donate a proton (H+) and a base is a substance that can accept a proton. Any proton in an organic molecule can potentially be donated. The most acidic proton in a molecule would be donated first. Any lone pair in an organic molecule can act as the proton acceptor. An acid (HA) reacts with a base (in this case H2O) to form the conjugate base of the acid (A-) and the conjugate acid of the
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Brief Historical Development and Contributions of Chemistry for Modern Civilization Introduction: As defined by Oxford Dictionary‚ Chemistry is the scientific study of the structure of substances‚ how they react when combined or in contact with one another and how they behave under different conditions . In other words‚ Chemistry is the study of the materials and substances of the world in which we live. The materials‚ which make up the earth‚ sea and air‚ are called raw materials. These include
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In a sawhorse projection‚ the backbone carbons are represented by a diagonal line‚ and the terminal carbons are shown in groups. In a staggered conformation the atoms and groups attached to each backbone carbon fit in the voids around the groups on the adjacent carbon. In an eclipsed conformation the groups and atoms on adjacent carbons are in line with each other. Steps in Drawing Sawhorse Structures Draw the sawhorse projection of 1-iodo-1‚2-dicholoro-2-fluoroethane in staggered
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All Tirthankaras and Kevaljnanis become siddha at the end of their life. They never return again to the cycle of pain‚ pleasure‚ life and death. The bound souls are further divided into mobile (trasa) and immobile (sthavara). Sthvara lives in the atoms of earth‚ water‚ fire and air and in the vegetable kingdom and have only one sense- that of touch. The mobile souls are again classified as those who are having two senses(worms)‚ three senses(ants)‚ four senses(bees) and five senses(higher animals
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Chemical Bonding and Molecular Structure MCQs: Test - 2 Sr. No. Questions Answers 1. The state of hybridization of the central atom and the number of lone pairs over the central atom in POCl3 are [WB JEE 2012] (A) sp‚ 0 (B) sp2‚ 0 (C) sp3‚ 0 (D) dsp2‚ 1 Answer: (C) 2. NiCl2{P(C2H5)2(C6H5)}2 exhibits temperature dependent magnetic behaviour (paramagnetic/diamagnetic). The coordination geometries of Ni2+ in the paramagnetic and diamagnetic states are respectively
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GajendraUjjenia Rajiv Gandhi Institute of Petroleum Technology Catalysis in Hydrotreating and Hydrocracking
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