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Characteristics of Solids. Review. One of over 100 types of pure substances from which all material are formed. Element → . The smallest particle of an element which all materials are formed. Atom →. Composition of an Atom. 3 types of Subatomic Particles 1 . Electrons →
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Review One of over 100 types of pure substances from which all material are formed Element → The smallest particle of an element which all materials are formed. Atom→
Composition of an Atom 3 types of Subatomic Particles 1. Electrons→ Is outside the nucleus and has a negative charge. 2. Protons → A positively charged particle in the nucleus of a Atom. It is ≈ the same mass as a Neutron 3. Neutron→ An uncharged particle located in the Nucleus of an Atom. It is ≈ the same mass as a Proton.
Definitions Nucleus→ The central portion of an atom – usually consisting of protons and neutrons. Periodic Table → An attempt to put the elements in some type of logical order, according to their atomic number and their chemical characteristics. Atomic Number→ A number representing the number of protons in an atom of an element.
Definitions Mass→ The amount of material (stuff) in an object. Mass is proportional to weight. Mass does not change when gravity changes while weight does. Families→ The name given to the 18 vertical columns of the Periodic Table. (Elements in a column will react similarly) Period → The 7 horizontal rows in the Periodic Table (Periods represent the number of layers of electrons in the atom.)
Example Silver: Symbol Ag Atomic Number of Silver is? 47 How many Protons does Ag have? 47 How many Electrons does AG have? 47 How many Electron layers? 5
Definitions Valence Electrons→ Electrons found in the outermost energy level or layer from the nucleus. (These electrons are involved in bonding.) Metal have a tendency to lose their valence electrons. Nonmetals try to obtain eight valence electrons.
Crystal Structures Crystal→ An object with a regularly repeating arrangement of its atoms. Crystal Lattice → The pattern that atomic particles form in a crystalline solid.
14differentCrystalline Systems, most metals fall into 3categories 1) Body-Centered Cubic (BCC) → A type of crystalline structure that is composed of 8 particles forming a cube with a 9th particle in the center of the cube.
14differentCrystalline Systems, most metals fall into 3categories 2) Face-Centered Cubic (FCC) → A type of crystalline structure that is composed of 8 particles forming a cube and 6 more particles that are each centered in 1 of 6 faces of the cube.
14differentCrystalline Systems, most metals fall into 3categories 3) Hexagonal-Close Packed (HCP) → A type of crystalline structure that is composed of 17 particles which are as closely packed as possible.
14differentCrystalline Systems, most metals fall into 3categories Unit Cell → The simplest and smallest arrangement of atoms that can be repeated to form a particular crystal.
Formation of Solids Allotropes→ Elements which occur in more than one form due to the way their atoms are packed. Iron @ room Temp → BCC Iron above 910°C → FCC Carbon can be a diamond or graphite depending on how its atoms are packed.
Metallic & Non-Metallic Elements Metal → Metals tend to lose electrons which changes them from neutral atoms to positive ions. Ion → An atom that has gained or lost a least one electron and has a negative or positive charge.
Metallic & Non-Metallic Elements Nonmetal → Nonmetals gain electrons which changes them from neutral atoms to negative ions. Ionic Bond → A bond resulting from the attractive force between ions of opposite charges. (Metal & Non Metal bond to form a compound). A very strong bond.
Type of Bonding Metallic Bond→ The force that hold solid metal together. Covalent Bond → A chemical attraction between 2 nonmetallic atoms that are sharing electrons. (Non-Metals).
Type of Bonding Molecules→ When 2 or more nonmetals share electrons to form covalent bonds. Van der Waal Forces → The weaker bonds that hold molecules to one another.
Type of Bonding Covalent Network Solids → Group of solids that contain only covalent bonds and are made of extremely large molecules. • Strong covalent bonds therefore very strong substances • High melting points • Examples are Diamond or Silicon Carbide