they have full outer shells of electrons, so they cant share other atoms' electrons
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how can you tell how many atoms of an element are in a compound when you see the chemical formula for that compound?
the number to the bottom right of the element symbol
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what do most atoms want in their outer shell in order to be stable?
eight electrons
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what do you call the little numbers that are written below and to the right of the chemical symbol?
a subscript
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what is a chemical formula?
a set of chemical symbols showing the elements present in a compound and their proportions
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what is a Lewis structure? (electron dot structure)
representation of the valence shell electrons in a molecule
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what is formed when two or more elements chemically combine?
a compound
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how do you know how many dots to place around a chemical symbol in a Lewis structure?
The number of dots equals the number of valence electrons in the atom
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What is a molecule?
a group of atoms bonded together
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what is a covalent bond?
one or more pairs of electrons between two atoms
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what is an ionic bond?
chemical bond formed when one atom gives up one or more electrons to another atom
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what is the difference between ionic and covalent bonding?
Covalent bonding involves the sharing of electrons between two or more atoms. Ionic bonds form when two or more ions come together and are held together by charge differences.
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when atoms form covalent bonds, do the acquire a charge?
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when you look at a chemical formula, how can you tell if the compound is ionic or covalent?
compounds that involve a binding with a non-metal will display ionic bonding
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how can you tell whether two elements will form an ionic or covalent bond?
If a compound is made from a metal and a non-metal, its bonding will be ionic
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what is a charge number?
value of an electric charge
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what do the charges of the ions in an ionic bond add up to?
the total overall charge is zero because the total positive charges are equal to the total negative charges.
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describe how to name an ionic compound
state the cation then the anion
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describe how to name a covalent compound
Name the non-metal furthest to the left on the periodic table by its elemental name, Name the other non-metal by its elemental name and an -ide ending, Use the prefixes mono-, di-, tri-.... to indicate the number of that element in the molecule
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how do you know what the charge number for an atom is?
By comparing the number of protons to the number of electrons
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what do you call the little numbers above and to the right of the chemical symbol?
superscript
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what is a polyatomic ion?
a covalent bonded set of two or more atoms
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what do the prefixes used in the naming of covalent compounds mean?
to indicate the number of atoms of that element
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how can you tell what the subscripts in an ionic chemical formula should be if you are only given the names of the two elements that combine?
Transpose only the number of the positive charge to become the subscript of the anion and the number only of the negative charge to become the subscript of the cation.
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when you are going to write a chemical formula, what does a roman numeral tell you?
indicates the charge and the oxidation state of the transition metal ion.
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how do you write formulas when polyatomic ions are involved?
When the formula unit contains two or more of the same polyatomic ion, that ion is written in parentheses with the subscript written outside the parentheses
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what does a roman numeral after an element mean?
the charge of the element
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potassium form a binary ionic compound with iodine. what is the name of this compound?
potassium iodide
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aluminium and chlorine combine in a 1 to 3 ratio, what is the chemical formula of this compound?
AlCl3
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what is the difference between carbon monoxide and carbon dioxide
they contain a different amount of atoms
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how many calcium, phosphorus, and oxygen atoms are present in calcium phosphate?
two atoms of phosphorus, three atoms of calcium and eight oxygen atoms.