Science Ch. 11-12
Word Equations
-The reactants are written on the left and the products on the right. -An arrow separates them. -You read the arrow as yields, gives, or reacts to produce. -Reactants → products
There are 5 general types of reactions:
-combination -decomposition -single-replacement -double-replacement -combustion.
Ionic Equations
-ionic charges must be balanced in a net ionic equation -spectator ions are left out of a net ionic equation
For a double-replacement reaction to occur, one of the following is usually true:
1. One of the products is only slightly soluble and precipitates from solution. 2. One of the products is a gas. 3. One product is a molecular compound such as water.
Combustion
A combustion reaction is a chemical change in which an element or a compound reacts with oxygen, often producing energy in the form of heat and light.
Double-replacement Reaction
A double-replacement reaction, which is a chemical change involving an exchange of positive ions between two compounds. They generally take place in aqueous solution and often produce a precipitate, a gas, or a molecular compound such as water.
___________________ is a conversion factor derived from the coefficients of a balanced chemical equation interpreted in terms of moles.
A mole ratio
Single-replacement
A single-replacement reaction is one in which one element replaces a second element in a compound.
__________________ tells the story of a chemical reaction.
Chemical Equation
What is a net ionic equation?
It indicates only those particles that take part in the reaction.
Chemical formulas must obey the ____________________________
Law of the conservation of Matter
_____________ are the new substances that are formed.
Products
_____________ are the starting substances in the reaction.
Reactants
What determines whether a precipitate forms when two solutions are ionic compounds are mixed?
Solubility of ionic compounds determine the formation of a precipitate
NaOH
Soluble
Decomposition
Some chemical reactions are the opposite of combination reactions. A decomposition reaction is a chemical change in which a single compound breaks down into two or more simpler products.
Combination
a chemical change in which two or more substances react to form a single new substance.
The reaction of aqueous solutions of silver nitrate and sodium chloride to form solid silver chloride and aqueous sodium nitrate is ____________
a double-replacement reaction
Many important chemical reactions take place in _____________________
aqueous solution
A chemical reaction is also described by a _______________________ in which each side of the equation has the same number of atoms of each element and mass is conserved.
balanced equation
A _____________ is a substance that speeds up the reaction but is not used up in the reaction.
catalyst
A ____________ is a representation of a chemical reaction; the formulas of the reactants (on the left) are connected by an arrow with the formulas of the products (on the right).
chemical equation
Chemists use a _____________ - a quick, shorthand notation - to convey as much information as possible about what happens in a chemical reaction.
chemical equation
The large numbers infront of some formulas are _______________
coefficient
In a chemical equation, only the ______________ can change
coefficients
An equation that shows dissolved ionic compounds as their free ions is called _____________
complete ionic equation
In any chemical change, mass is ____________.
conserved
You can use these ions to write a complete ionic equation, an equation that shows dissolved ionic compounds as _________________.
dissociated free ions
The number of atoms of each element on both sides of the equation must be ________________ because matter can not be created or destroyed
equal
A ____________ can also replace another _____________ from a compound.
halogen
Fe(OH)3
insoludable
HgSO4
insoludable
____________________ are used to convert between a given number of moles of a reactant or product to moles of a different reactant or product.
mole ratios
Chemists use balanced chemical equations as a basis to calculate how _______________________________________
much reactant is needed or how much product will be formed in a reaction.
The __________ is an equation for a reaction in solution that shows only those particles that are directly involved in the chemical change.
net ionic equation
As _________________, the bonds holding the atoms together are broken, and new bonds are formed.
reactants are converted to products
Whether one metal will displace another metal from a compound depends upon the ____________ of the two metals.
relative reactivities
A ___________________ is a chemical equation that does not indicate the relative amounts of the reactants and products.
skeleton equation
An ion that appears on both sides of an equation and is not directly involved in the reaction is called a _____________.
spectator ion
___________ is not directly involved in a reaction
spectator ion
The calculations of quantities in chemical reactions is called ____________________.
stoichiometry
When you rewrite an equation leaving out the spectator ions, you have ________________.
the net ionic equation
Most ionic compounds, the reactants and one of the products dissociate, or separate, into cations and anions when they dissolve in ______.
water