Chem - Ch 11 Flashcards
what is a chemical equation
an expression representing a chemical reaction
what is a catalyst
a substance that increases the rate of reaction by lowering the activation-energy barrier; the catalyst is not used up in the reaction
is a catalyst a reactant or a product
neither
what is a balanced equation
a chemical equation in which mass is conserved
each side of the equation has the same number of atoms of each element
what is a skeleton equation
a chemical equation that does not indicate the relative amounts of reactants and products
what is a coefficient
a small whole number that appears in front of a formula in a balanced chemical equation
how do you write a skeleton equation
write the chemical formulas for the reactants to the left of the arrow and the formulas for the products to the right
what are the steps for writing and balancing a chemical equation
first write the skeleton equation, then use coefficients to balance the equation so it obeys the law of conservation of mass
What is present in the reactants of every combustion reaction
a hydrocarbon and oxygen (O2)
What makes up a hydrocarbon
hydrogen, carbon, and possibly oxygen
What is always present in the products of every combustion reaction
carbon dioxide and water
how would you identify a combustion reaction
a hydrocarbon and oxygen as the reactants, carbon dioxide and water as the products
how would you predict the products of a combustion reaction
always carbon dioxide and water
if not complete, carbon and carbon monoxide may also be products
what is always present in the reactants of acid-base reactions
an acid and a base
-a hydrogen compound and an OH compound
What is always present in the products of an acid base reaction
water and another compound
what is hydrogen always paired with in its compound in the reactants of acid-base reactions
an anion
what is OH always paired with in its compound in the reactants of acid-base reactions
a cation
what are acid-base reactions a subsection of
double replacement reactions
what are acid-base reactions often called
neutralizations
why are acid-base reactions always called neutralizations
they make things safe
how would you identify an acid-base reaction
looks like a DR reaction -2 compounds as reactants -2 compounds as products BUT will include an acid and a base -acid will always have hydrogen (written 1st) -base will always have OH (written 2nd)
what is always present in an acid
hydrogen
What happens in a combination/synthesis reaction
two or more elements or compounds combine to form one product
what happens in a decomposition reaction
one compound breaks into elements or smaller compounds
what happens in a single replacement reaction
part of an ionic compound is removed and replaced by a new element
what happens in a double replacement reaction
ionic compounds dissolved in water switch partners
how do you predict the products of an acid-base reaction
same way you do a double replacement reaction
one will always end up being water
what does soluble mean
will dissolve in water
what does insoluble mean
won’t dissolve in water
what is a precipitate
insoluble substance that forms in a reaction
what is the abbreviation a precipitate
ppt
what do we call ionic compounds
salts
what will soluble ionic compounds do
dissolve in water and break up into their ions
what is a combination reaction
a chemical change in which 2 or more substances react to form a single new substance
what is another name for a combination reaction
synthesis
what is a decomposition reaction
a chemical change in which a single compound is broken down into 2 or more simpler products
What is a single replacement reaction
a chemical change in which one element replaces a second element in a compound
how do you know which element gets kicked out in a single replacement reaction
the metal kicks out the metal, the nonmetal kicks out the nonmetal
how do you know if a single replacement reaction will actually take place or not
if the element alone on the reactant side is higher on the activity series than the element it’s kicking out
what is a double replacement reaction
a chemical change that involves an exchange of positive ions between two compounds
what is the activity series
a list of elements in order of decreasing activity
what is a combustion reaction
a chemical change in which an element or a compound reacts with oxygen
what does a combustion reaction often produce
energy in the form of heat and light
what happens to the charges in a double replacement reaction
they stay the same throughout
what are cations always paired with in a double replacement reaction
anions
how many reactants do decomposition reactions have
one (its a compound)
how many products do combination reactions have
one (its a compound)
how can you identify a combination reaction
there is only on product (a compound)
2 (often) elemental reactants
how can you predict the products of a combination reaction
a compound of the 2 reactants
how can you identify a decomposition reaction
one reactant (a compound) 2 (often) elemental products
how can you predict the products of a decamp reaction
the separate elements from the reactant compound
how can you identify a single replacement reaction
both the reactants and products consist of an element and a compound
how can you predict the products of a single replacement reactions
the elemental reactant replaces the metal/nonmental (whatever the element is) in the compound
how can you identify a double replacement reaction
the 2 reactants are compounds, the 2 products are also compounds
how can you predict the products of a double replacement reaction
the 2 outsides go together, the 2 insides go together
if a combustion reaction is not complete, what may be the additional products
elemental carbon (soot) and carbon monoxide gas
what is a complete ionic equation
an equation that shows dissolved ionic compounds as disassociated free ions
what is a spectator ion
an ion that is not directly involved in a chemical reaction
what is a net ionic equation
an equation for a reaction in solution showing only those particles that are directly involved in the chemical change
how can you predict the formation of a precipitate in a double replacement reaction
by using the general rules for solubility of ionic compounds
