atoms of 1 or more substances are rearranged to form different substances
evidence of chemical change
temp change, color change, gas bubbles, precipitate-solid resulting from 2 clear liquids
-law of conservation-matter is neither created nor destroyed (matter is conserved during a reaction)
word equations
written out instructions of an equation
skeleton equations
uses chemical formulas to identify reactants and products
chemical equations
must show how law of conservation of matter is obeyed
# atoms of reactants=?
# atoms of products
coefficient
number written in front of a reactant or product.
-describes the lowest whole ration of amounts of all reactants and products
synthesis reaction
also called composition reactions; 2 elements or simple compounds combine to form new compounds; generally compounds produced are larger or more complex than the reactants
combustion reactions
normally involve a substance reacting rapidly with oxygen gas, releasing heat and light
decomposition
a single compound breaks down into 2 or more elements or less complex compounds; most are endothermic.
metallic chlorates
break down to metal chloride and oxygen gas
carbonates
break down to metal oxide and carbon dioxide
metallic hydroxides
break down to metal oxide and water
certain acids
weak acids break down to non-metal oxide and water