Flashcards in Unit 2-Chemical Changes Deck (23)
balance chemical equations
what are the five pieces of evidence for a chemical change
formation of gas,
release or absorption of energy,
determine the type of reaction and predict the products
endothermic versus exothermic
endothermic reactions require energy
exothermic reactions create energy
what is the word equation for methane?
what is another way to write H2O?
define chemical change.
what happens in a chemical change?
A chemical change is a change in which at least one new substances formed, with different physical and chemical properties then the starting materials
New products are created
A chemical reaction in which two or more substances combine to form a more complex sentence
Chemical reaction in which compound is broken down into two or more simpler substances
The reaction of a substance with oxygen to produce oxides and energy
most commonly used to produce heat
Combustion of a hydrocarbon produces...
H2O and CO2
reaction of an element with the compound to bring us a new element and a new compound activity series will be used
why is hydrogen placed with the metals on the activity series?
hydrogen acts like a metal so it is on the list of metals (loses electrons) it becomes positively charged
how to use activity series
anything that is higher on the activity series will form the compound by displacement
this is the reaction in which compounds rearrange and form new compounds.
solutions that may or may not have precipitates
a double displacement reaction between an acid and a base to produce an ionic compound (a salt) and water
put a 1 before compounds with no number out front
what occurs during a chemical change?
a new substance is created
bonds break or form because of their attractive forces
endothermic and example
The reaction needs a continuous supply of energy put into the system
example copper he did over the Bunsen burner the reaction stopped when the heat stopped
exothermic and example
A reaction that releases much more energy then what was put into the system
acid rain causes
factors that lead to acid rain are transportation, heating homes, and coal burning factories
what is the equation for acid rain?