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Key Facts & Summary of Enthalpy Changes The enthalpy of a chemical system refers to the "heat content" of the system. Enthalpy is given the symbol H Enthalpy change refers to the amount of heat released or absorbed when a chemical reaction and it is given the symbol ΔH A reaction is exothermic when it ...
Key Facts & Summary of Electron Structure Lewis structures are diagrams that show the bonding between atoms of a molecule and the lone pairs of electrons. The electronic structure is the arrangement of electrons in energy levels around an atomic nucleus The s orbital can be occupied by no more than a pair of electrons. ...
Key Facts & Summary Elements are composed of one type of atom. An element cannot be decomposed into simple substances Compounds can be decomposed into elements Compounds are composed of two or more types of atoms A Chemical formula is a representation of the number of atoms of each element that makes a compound. The ...
Key Facts & Summary of Chemical Equilibrium Chemical equilibrium is defined as the dynamic condition reached by a reversible reaction when the direct reaction and the inverse reaction occur simultaneously. A reversible reaction can proceed in both forward and backward directions. Equilibrium is reached when the rate of the forward reaction equals the rate of ...
Key Facts & Summary for Bonds and Structures There are 4 main chemical bonds: ionic, covalent, polar and hydrogen bond. Electronegativity is the property of an atom to attract a shared pair of electrons (or electron density) towards itself. An ionic bond involves a transfer of an electron between two atoms A covalent bond involves ...
Key Facts & Summary of the Basic Concepts of Organic Chemistry Organic chemistry is the study of the structure, properties, composition, reactions, and preparation of carbon-containing compounds. Covalent bonding is a chemical bond that involves the sharing of electron pairs between atoms. Lewis model are diagrams that show the bonding between atoms of a molecule ...
Key Facts & Summary Atoms are made of neutrons, protons and electrons. Neutrons and protons are situated in the nucleus, while the electrons orbit around the nucleus. Isotopes are versions of an element with a different number of neutrons. The number of protons for different isotopes is the same and does not change. Some isotopes ...
Key Facts & Summary of Amount of Substances Molar Mass is the mass in grams of 1 mole of a substance and is given the unit of g mol-1 The mole is the amount of substance in grams that has the same number of particles as there are atoms in 12 grams of carbon-12. One ...
Key Facts & Summary Alkenes are hydrocarbons containing a carbon–carbon double bond. All the alkenes with 4 or more carbon atoms in them show structural The carbon-carbon double bond doesn't allow any rotation about it, (cis-trans isomerism). Shared electrons in the double bond are called pi electrons and they create a pi bond. The electrons ...
Key Facts & Summary Alkanes are hydrocarbons in which all the bonds are single bonds Isomeric alkanes: the butanes. IUPAC rules assign names to unbranched alkanes. Carbon atoms are classified according to their degree of substitution by other carbons. Cycloalkanes also only contain carbon-hydrogen bonds and carbon-carbon single bonds, but the carbon atoms are joined ...
