Unit 8 Flashcards
What are chemical reactions represented by?
Chemical equations. In a chemical equation there is a reactant and a product.
Reactant –> Product
In a chemical reaction, atoms are
Neither created nor destroyed which means the reactant and product sides of the equation have the same number of each atoms.
What does “(s)” symbol stand for in a balanced equation? (Shows up as a subscript next to the amount of element)
Solid
What does “(l)” symbol stand for in a balanced equation? (Shows up as a subscript next to the amount of element)
Liquid
What does “(g)” symbol stand for in a balanced equation? (Shows up as a subscript next to the amount of element)
Gas
What does “(aq)” symbol stand for in a balanced equation? (Shows up as a subscript next to the amount of element)
Aqueous (dissolved in water)
What should you change when balancing equations?
The coefficients and NEVER the subscripts.
Coefficients are never in the middle of a molecule, always in the front.
What are the naturally diatomic elements?
Bromine, Iodine, Nitrogen, Chlorine, Hydrogen, Oxygen, Fluorine.
HI BrO FNCl
Synthesis reaction
A reaction where two or more reactants form ONE product.
Decomposition reaction
A r.eaction where ONE reactant produces two or more products
Single replacement reaction
element + compound —> element + compound
One element and one compound on each side.
Double replacement reaction
compound + compound —> compound + compound
two compounds on each side. The elements of the compounds switching places
Combustion reaction
A reaction with oxygen.
Hydrocarbon + O2 —> CO2 + H2O
Neutralization reaction
Acid-Base reaction. When an acid (H+) and a base (OH-) react to form water.
Water is in the products.
Oxidation-Reduction reaction
Transfer of electrons (change in electron structure of the ions or atoms involves)
Any reaction where an atom is unbonded on one side and bonded on the other.
ALWAYS single replacement
NEVER double replacement
Oxidation is…
Loss of electrons (becoming more positive)
Reduction is…
Gain of electrons (becoming more negative)
What is stoichiometry?
Defined as the quantitative relationship between two or more substances especially in processes involving physical or chemical change.
Steps to solving ANY stoichiometry problem?
- BALANCE the equation
- Convert given to MOLES
- Convert from one molecule to another using moles to moles
- Convert to what is being asked for
How to find percent yield?
(actual yield / theoretical yield) 100
Theoretical yield is…
grams unless otherwise stated
What is the limiting reactant?
The reactant that is least in amount.
How to find the excess reactant? (once the limiting reactant is used up what is left of the other reactants?)
Using the limiting reactant as the GIVEN (of a stoichiometry problem) and the other reactant as what you want to solve for.
