The Periodic Table
Why Do Atoms Combine?
How Elements Bond
How Elements Bond 2
Chemical Formulas and Equations
100
Horizontal row of elements in the periodic table whose properties change gradually and predictably.
What is a period?
100
Area where negatively charged electrons, arranged in energy levels, travel around an atom's nucleus.
What is an electron cloud?
100
Combination of chemical symbols and numbers that indicates which elements and how many atoms of each element are present in a molecule.
What is a chemical formula?
100
Attraction that holds oppositely charged ions close together.
What is an ionic bond?
100
Process that produces chemical change, resulting in new substances that have properties different from those original substances.
What is a chemical reaction?
200
Family of elements in the periodic table that have similar physical or chemical properties.
What is a group?
200
Force that holds two atoms together.
What is a chemical bond?
200
Atom that is no longer neutral because it has gained or lost an electron.
What is an ion?
200
Bond formed when metal atoms share their pooled electrons.
What is a metallic bond?
200
Substance that exists after a chemical reaction.
What is a product?
300
Element that does not conduct electricity as well as a metal but better than a non-metal.
What is a semiconductor?
300
Chemical symbol for an element, surrounded by as many dots as there are electrons in its outer energy level.
What is an electron dot diagram?
300
Chemical bond formed when atoms share electrons.
What is a covalent bond?
300
Neutral particle formed when atoms share electrons.
What is a molecule?
300
Substance that exists before a chemical reaction.
What is a reactant?
400
Element in group 17 of the periodic table.
What is a halogen?
400
The different positions of an electron in an atom.
What is an energy level?
400
A pure substance that contains two or more elements.
What is a compound?
400
Type of bond formed when two atoms share electrons equally.
What is a non-polar bond?
400
Chemical reaction in which heat energy is released.
What is an exothermic reaction?
500
Element in group 18 of the periodic table.
What is a noble gas?
500
Expression for determining how many electrons an energy level can hold.
What is 2n^2?
500
Bond resulting from an unequal sharing of electrons.
What is a polar bond?
500
Type of bond formed between the nitrogen atoms in nitrogen gas (N2).
What is a triple bond?
500
Chemical reaction in which heat energy is absorbed.
What is an endothermic reaction?
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