8th Grade-Chemical Formulas & Equations


Terms in this set (...)

Chemical Change
change in a substance through chemical reactions to form new substances with different properties
Chemical Equation
a representation of a chemical reaction that uses symbols to show the relationship between the reactants and the products
the number in front of a chemical formula in an equation that indicates how many molecules or atoms of each reactant and product are involved in a reaction
Chemical Reaction
breaking of old and formation of new chemical bonds that result in new substances
a substance made up of atoms of two or more different elements joined by chemical bonds in definite proportions
Conservation of Mass
the principle stating that matter is not created or destroyed during a chemical reaction; the number of atoms and mass at the beginning of a reaction must equal the number at the end of the reaction
two or more atoms held together by covalent bonds
Physical Change
a change that does not involve a chemical reaction such as a change in size, shape, or state of matter; the identity of the substance remains the same
a chemical substance formed as a result of a chemical reaction found to the right of the yield sign
a chemical substance that is present at the start of a chemical reaction found to the left of the yield sign
a number in a chemical formula written to the lower right of a symbol that tells the number of atoms in a molecule or the ratio of elements in a compound
Yield Sign
the arrow in the middle of a chemical equation that separates reactants and products
any of the more than 100 known substances that cannot be separated into simpler substances and that singly or in combination constitute all matter; a pure substance made up of only one kind of atom
matter that has the same composition and properties throughout
Chemical Formula
A formula using symbols and numbers that gives the elements in a compound and the ratio of atoms.
A physical property that measures how much mass is contained in a given volume.
Physical Property
A quality or condition of a substance that can be observed or measured without changing the substance's composition
Chemical Property
A property of matter that describes a substance's ability to participate in chemical reactions or its ability to change into different substances
A solid that forms from a solution during a chemical reaction.