Chemical Reactions Chapter 7 Flashcards
What rearranges atoms?
Chemical reactions
occur when substances go through chemical changes to form new substances.
Chemical Reactions
a substance or molecule that participates in a chemical reaction
Reactant
A substance or molecule that forms in a chemical reaction
Product
Label the products and the reactants
NaCl + AgNO3 -> AgCl + NaNO3
Stuff on left of arrow = reactant
Stuff on right of arrow = product
Signs that a chemical change has taken place
Change in color Production of gas New compounds form Production of sound Light or heat is given off
____ must be added to break bonds.
Energy
____ releases energy.
Forming bonds
Sometimes energy is transferred as ___ or ___, ___ or ___.
Heat or electricity
Sound or light
Energy is conserved in ____.
Chemical reactions
the energy released when a chemical compound reacts to produce a new compound
Chemical Energy
Reactions that release energy are called ____.
Exothermic
Reactions that absorbed energy are called _____.
Endothermic
_____ is an example of an endothermic reaction.
Photosynthesis
Look at the graphs on page 222.
A chemical equation uses _____ to represent a chemical reaction and shows the relationship between the reactants and products of a reaction.
Symbols
Balanced chemical equations account for the _______.
Conservation of Mass
A balanced equation tells you the ___, or proportion of reactants and products, in a chemical reaction.
Mole ratio
Do we mess with the subscripts?
NEVER!!!!!!!!!!!!!!!!!!!!!
Ever!!!!!!!!!!!!!!!!
How do we balance chemical equations?
Balance one element at a time
Use coefficients in the front of the chemical formula
There are __ general types of reactions.
5
These reaction types follow _____.
Set patterns
What can the patterns help you with?
Predicting the products of the chemical reactions
- a reaction in which two or more substances combine to form a new compound
Synthesis Reaction
Synthesis Reaction:
A + B ->
AB
What is a more complex compound in a synthesis reaction? The end product or the reactant?
The end product
-a reaction in which a single compound breaks down to form two or more simpler substances
Decomposition Reaction
Decomposition Reaction:
AB ->
A + B
Reactions in which substances are broken apart
Decomposition Reaction
-the oxidation reaction of an organic compound in which heat is released
Combustion Reaction
Combustion Reaction:
2CH(4) + 4O(2) ->
2CO(2) + 4H(2)O
In a Combustion Reaction, at least one product of the reaction contains ___.
Oxygen
In combustion, the products depend on _____.
How much oxygen is present
Read the bottom section of page 232 and look at the combustion reaction on page 192.
- a reaction in which one element or radical takes the place of another element or radical in a compound
Single- displacement reaction
Single-displacement Reactions:
AX+B->
BX+A
In a Single-displacement Reaction, a ___ element will take the place of a ____ one.
More reactive
Less reactive
- a reaction in which a gas, a solid, precipitate, or a molecular compound forms from the apparent exchange of atoms or ions between two compounds
Double-displacement reaction
Double-displacement reactions:
AX+ BY ->
AY + BX
____ and ____ can be understood as changes in the numbers of electrons that atoms have.
Free-radical reactions and redox reactions
What reactions have electrons available for bonding?
Free-radicals
-an atom or a group of atoms that has one unpaired electron (fragment)
Free radical
-any chemical change in which one compound is oxidized (loses electrons) and another is reduced (gains electrons)
Oxidation- Reduction Reaction
Most reactions go faster at ____ temps.
Higher
____ speeds up the reactions.
A large surface are
____ of reactants react faster.
Higher concentrations
What would be the best way to make a larger surface area?
Crush it into a powder
Reactions are faster at ___ pressure.
Higher
___ a reaction often makes it react faster.
Stirring
____ change the rate of chemical reactions.
Catalysts
- a substance that changes the rate of chemical reactions but is not changed by the reaction
Catalyst
____ are catalysts that slow down a reaction.
Inhibitors
___ are biological catalysts.
Enzymes
Enzymes are ___ that ___ metabolic reactions in plants and animals without being permanently changed or destroyed.
Protein
Speeds up
- a part, substance, or element that lies beneath and supports another part, substance, or element
Substrate
A reaction that is able to reverse itself often results in an ____.
Equilibrium system
Systems in equilibrium respond to _____.
Minimal change
Le Chatelier’s Principle predicts changes in ____.
Equilibrium
-If a change is made to a system in chemical equilibrium, the equilibrium shifts to oppose the change until a new equilibrium is reached.
Le Chatelier’s Principle
