By, Olivia Pierson
Chemical Reactions: The Basics
 Signs of a Chemical Reaction
 Reactants & Products
 Law of Conservation of mass
 Energy & Chemical Reactions
 Exothermic Reactions
 Activation Energy

Table of Contents
What part of atoms are affected?
-the electrons are affected
What is happening during a
chemical reaction?
-one or more bonds between
atoms are either broken or new
ones are formed
Chemical Reactions:
The Basics
Information: www.wikianswers.com
 Change
in
 Change in
 Change in
 Change in
temperature
form
color
scent
Signs of a
Chemical Reaction
Information: www.wikianswers.com
What are Reactants?
-reactants are two or more elements that
chemically interact to form a new
substance.
What is a Product?
-a product is the result of the experiment,
what is produced at the end
Reactants &
Products
Information: www.wikianswers.com
Law of Conservation
of Mass
Energy cannot be created nor destroyed but it can
change forms
(solid, liquid, gas, plasma)
How it is related to a chemical reaction is the
energy is not created nor destroyed but it
changes forms, such as going from a solid to a
liquid, liquid to gas, or solid to gas, liquid to
solid, gas o solid…ect…
http://wiki.answers.com/Q/What_is_the_law_of_c
onservation_of_mass&alreadyAsked=1
Law of
Conservation of
Mass
The Law of Conservation of
Mass was discovered by
Antoine Laurent Lavoisier
in 1785
Image: https://images.google.com/Lavoisier
Energy & Chemical
Reactions
What is an endothermic reaction?
-an endothermic reaction, for example, is when
is when you mix two solids called
barium hydroxide and ammonium
salt.
When mixed they dissolve together
Into water of hydration, therefore
They become very cold.
Image: http://genchem.chem.wisc.edu/demonstrations/Movies/endosm.gif
Exothermic Reactions
What is an exothermic reaction?
-a candle for example
When enough heat is applied to a candle it
starts to oxidize. The paraffin reacts with
the water resulting in carbon dioxide and
water, also heat and light. The reaction
creates visible light, the flame.
Information: http://chemistry.about.com
What is chemical potential energy?
-chemical potential energy is energy
which is stored in the chemical
bonds of the atoms in a molecule.
When the bonds are re-arranged,
energy can be released.
Chemical Potential
Energy
Information: http://www.psd70.ab.ca/sgchs/Sc10/potent.html
Activation Energy is the energy
needed by a system to initiate a
particular process. It is often used to
denote the minimum energy needed
for a specific chemical reaction to
occur. Information: http://www.bio-medicine.org
Activation Energy
Synthesis Reactions
What is happening in a synthesis reaction?
-In a synthesis reaction, two or more
substances combine to form another
substance
-It’s the formation of a complex
compound by the combination of two or
more simpler compounds, elements, or
radicals.
http://wiki.answers.com/Q/What_is_a_s
ynthesis_reaction&alreadyAsked=1
Image: http://www.usoe.k12.ut.us/CURR/Science/sciber00/8th/matter/images/SYNTHES.GIF
What is happening in a decomposition
reaction?
-A decomposition reaction is where one single
compound breaks down into two or more simpler
chemicals. An example of this is the
decomposition of zinc carbonate, represented by
the equation:
-ZnCO3(s) ZnCO(s) + CO2(g)
http://wiki.answers.com/Q/If_heat_must_be_adde
d_to_a_chemical_reaction_for_the_reaction_to_ta
ke_place_the_reaction_is&alreadyAsked=1&rtitle=
What_is_a_decompostition_reaction
Image: www.chemistryexplained.com
Decomposition Reactions
Combustion Reactions
What is happening in a combustion
reaction?
-A combustion reaction is a reaction in
which a substance reacts with oxygen and
heat is released.
http://wiki.answers.com/Q/What_is_a_combustion_rea
ction&alreadyAsked=1
Image: http://www.process-heating.com/PH/2002/08/Files/Images/116295.gif

A single replacement is when a single
uncombined element replaces another in a
compound. Two reactants yield two products.
For example when zinc combines with
hydrochloric acid, the zinc replaces hydrogen.
The chemical equation for this single
replacement reaction looks like:

Zn + 2HCl ---> ZnCl2 + H2
Single Replacement
Reaction
http://wiki.answers.com/Q/What_is_a_single_repla
cement_reaction&alreadyAsk
A double replacement reaction is when
two elements switch places in a chemical
reaction. An example would be...
 NaSOU4+PoBNF2=>PoBOU4+NaSNF2 The
NaS and the PoB switched places.

Double
Replacement
Reactions
http://wiki.answers.com/Q/What_is_a_double_rep
lacement_reaction&alreadyAsked=1