2Atoms – The basic building blocks of all thesubstances in theuniverse. All thingsare made up ofatoms.
3MATTER is never created or destroyed, it only changes form.
4Elements – Are made of one kind. of atom; grouped. together Elements – Are made of one kind of atom; grouped together. The periodic table is 110 different type of elements.Like atoms make up elements110 elements make up all the known substances on earth!!!(name something)
5Atoms contain one or more PROTONS, NEUTRONS, and ELECTRONS
6Electrons Protons and neutrons make up the nucleus of an atom. Electrons “float” around the nucleus of an atom.nucleusElectrons
7balance the charge of the atom to neutral. The nucleus of the atom is positively charged (+). The negatively (-) charged electrons surround the nucleus tobalance the charge of the atomto neutral.The number of protons equals the number of electrons.
8The number in the right corner of each element represents the amount of protons that element has……thus the amount of electrons.
10Electrons circle around the nucleus in shells or energy levels. As an element looses an electron it looses energy and as an element gains electrons it gains energy.Each circle or shell is limited to how many electrons it can hold.
12Valence electrons – electrons in the outermost energy level of an atom. The valence shell can have 1 to 8 electrons in it depending on its place on the periodic table. Elements to the left have 1 and elements to the right have 8.
13Electrons in valance shells that are not full will either gain electrons to become full or give up electrons allowing its outer shell to be lowered to its next lowest level (which is full).
15Ionic bonding – bonding that involves a transfer of electrons Ionic bonding – bonding that involves a transfer of electrons. Elements tend to want a full outer shell, thus giving up electrons to other elements or gathering electrons from other elements.Example Na+ and Cl-Mg2+ and O2-
16Ionization energy – is the process of removing electrons and forming ions. Ions – a charged atom, positive or negative charge.The fewer electrons per shell the less energy needed to pull the electrons away from that element.The greater the amount of electrons per shell the higher the ionization energy needed to “pull” the electrons away from that element.
17like repels like and opposites attract. Crystal Lattice – is the placement of ions in an ionic compound that results in a regular, repeating arrangement.Because?like repels like and opposites attract.
19Compound – A substance made of two or more elements chemically combined in a specific ratio, or proportion.Mixture – Two or more substances that are mixed together but not chemically combined.Solution – A well mixed mixture.
20Physical Change – A change that alters the form or appearance of a material but does not make the material into another substance.Chemical Change – A change in matter that produces a new substance.
21Precipitate – A solid that forms from a solution during a chemical reaction. Molecule – A particle made of two or more atoms that are covalently bonded together.The key characteristic of a chemical reaction is the production of new materials that are chemically different from the starting materials.· Chemical reactions occur when chemical bonds break or when new bonds form.
22precipitate of cadmium sulfide forms from clear solutions of sodium sulfide and cadmium nitrate.
23Covalent bondsCovalent bonding – Bonding of atoms in which electrons are shared.exp. H HElectron dot diagram – chemists way of expressing the sharing or placement of electrons.
24Diatomic elements – Covalent bonding that takes place between atoms of the same element. (hydrogen, bromine, oxygen, iodine, and nitrogen)Polyatomic ion – A group of covalently bonded atoms that act like a single atom when combining with other atoms. (OH1- hydroxide) pg 24.
25Metallic BondingMetallic bond – bond formed by atoms of metals, in which the outer electrons of the atoms form a common electron cloud.The atoms of metals form metallic bonds
26metals are elements that give up electrons easily. Metals are ductile, malleable, and good conductors.Ductile – The ability to be stretched without breaking.Malleable – the ability to be flattened or hammered and still hold together.Conductor – something that has the ability to carry heat or electricity.
27OXIDATION NUMBEROxidation number - is the number of electrons an atom gains, loses, or shares when it forms a chemical bond.· Na looses one electron thus making atom overall charge positive· Mg looses two electrons thus making atom charge positive· B3+
28· N3- gains three electrons making overall charge negative · P3-· O2- gains two electrons making overall charge negative· Cl1-The sum of oxidation numbers must equal zero when combining elements into compounds.Na 1+ and Cl 1- equal zero NaCl.