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States That Each Electron Occupies the Lowest Energy Orbital Available

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States That Each Electron Occupies the Lowest Energy Orbital Available Unit 4 Vocabulary Aufbau principle – states that each electron occupies the lowest energy orbital available. Electron affinity – energy released when an electron is added to an atom to form an ion. Electron orbitals – the different energy levels filled by electrons within an atom (s, p , d, and f). Electron configuration – The arrangement of electrons in an atom, which is prescribed by three rules – the Aufbau principle, the Pauli exclusion principle, and Hund’s rule. Electron-dot structure – Consists of an element’s symbol, representing the atomic nucleus and inner-level electrons; that is surrounded by dots, representing the atom’s valence electrons. Hund’s rule – states that single electrons with the same spin must occupy each equal-energy orbital before additional electrons with opposite spins can occupy the same orbitals (electrons fill empty orbitals before they pair up). Ion – negatively or positively charged atom (monatomic). Polyatomic Ion – negatively or positively charged group of atoms. Ionic bond – bond in which one or more electrons are given by one atom to another. Lewis dot structure – atomic symbol with dots showing valence electrons. Metallic bond – bond in which the valence electrons are shared among all the atoms in the metal. Molecular geometry – the 3D shape of a covalent molecule as determined by shared and unshared electrons. Octet rule – elements other than transition metals tend to react so that each atom has eight electrons in its outer (valence) shell; i.e. orbitals are full. Oxidation number – the positive or negative charge of a monatomic ion (for monatomic ions it is the charge on the ion). Pauli exclusion principle – states that a maximum of two electrons can occupy a single atomic orbital but only if the electrons have opposite spins. Polar covalent bond – a type of bond that forms when electrons are not shared equally due to differences in electronegativity (in a 3D non-symmetrical molecule, the unequal sharing does NOT cancel out, so that there is partial positive area and a partial negative area). Non-polar covalent bond – a type of bond that forms when electrons are not shared equally due to differences in electronegativity (in a 3D symmetrical molecule the unequal sharing cancels out and the molecule is non-polar). VSEPR (Valence Shell Electron Pair Repulsion) Theory – which is based on an arrangement that minimizes the repulsion of shared and unshared pairs of electrons around the central atom (unshared electron pairs of atoms in covalent molecules repel each other). Unit 4 Vocabulary Aufbau principle Electron affinity Unit 4 Vocabulary Electron orbitals Electron configuration Unit 4 Vocabulary Electron-dot structure Hund’s rule Unit 4 Vocabulary Ion Polyatomic Ion Unit 4 Vocabulary Ionic bond Lewis dot structure Unit 4 Vocabulary Metallic bond Molecular geometry Unit 4 Vocabulary Octet rule Oxidation number Unit 4 Vocabulary Pauli Exclusion Principle Polar covalent bond Unit 4 Vocabulary Non-polar covalent bond VSEPR (Valence Shell Electron Pair Repulsion) Theory Unit 4 Vocabulary Definition: states that each electron occupies the lowest energy orbital available. Unit 4 Vocabulary Definition: energy released when an electron is added to an atom to form an ion. Unit 4 Vocabulary Definition: the different energy levels filled by electrons within an atom (s, p, d, and f). Unit 4 Vocabulary Definition: The arrangement of electrons in an atom, which is prescribed by three rules – the Aufbau principle, the Pauli exclusion principle, and Hund’s rule. Unit 4 Vocabulary Definition: Consists of an element’s symbol, representing the atomic nucleus and inner- level electrons; that is surrounded by dots, representing the atom’s valence electrons. Unit 4 Vocabulary Definition: states that single electrons with the same spin must occupy each equal-energy orbital before additional electrons with opposite spins can occupy the same orbitals (electrons fill empty orbitals before they pair up). Unit 4 Vocabulary Definition: negatively or positively charged atom (monatomic). Unit 4 Vocabulary Definition: negatively or positively charged group of atoms. Unit 4 Vocabulary Definition: bond in which one or more electrons are given by one atom to another. Unit 4 Vocabulary Definition: atomic symbol with dots showing valence electrons. Unit 4 Vocabulary Definition: bond in which the valence electrons are shared among all the atoms in the metal. Unit 4 Vocabulary Definition: the 3D shape of a covalent molecule as determined by shared and unshared electrons. Unit 4 Vocabulary Definition: elements other than transition metals tend to react so that each atom has eight electrons in its outer (valence) shell; i.e. orbitals are full. Unit 4 Vocabulary Definition: the positive or negative charge of a monatomic ion (for monatomic ions it is the charge on the ion). Unit 4 Vocabulary Definition: states that a maximum of two electrons can occupy a single atomic orbital but only if the electrons have opposite spins. Unit 4 Vocabulary Definition: a type of bond that forms when electrons are not shared equally due to differences in electronegativity (in a 3D non- symmetrical molecule, the unequal sharing does NOT cancel out, so that there is partial positive area and a partial negative area). Unit 4 Vocabulary Definition: a type of bond that forms when electrons are not shared equally due to differences in electronegativity (in a 3D symmetrical molecule the unequal sharing cancels out and the molecule is non-polar). Unit 4 Vocabulary Definition: which is based on an arrangement that minimizes the repulsion of shared and unshared pairs of electrons around the central atom (unshared electron pairs of atoms in covalent molecules repel each other). .
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