2.8 Compounds: Formulas, Names, Masses Flashcards
What is the rule for all ionic compounds when naming them?
Cation/ positive ion comes first then anion/ negative ion second
what is the rule for naming cations and anions of all binary ionic compounds?
The name of the metal is the name of the cation and the name of the anion has (suffix -ide) added to the end of the metal
ex: anion formed from bromine = bromide
full example: a compound formed by metal calcium and nonmetal bromine becomes calcium bromide
what is a formula unit?
The chemical unit of a compound that contains the relative numbers of cations and anions in the compound
True or false Transition elements can form more than one ion?
TRUE
True or False: main group elements and a few transition metals form an ion with only one charge
TRUE
Monatomic _____ or elements in the same _____ group have the _______ ionic charge?
- ions
- main
- ionic
Alkali metals and Fr form ions with a a _____ charge and the halogens and I form ions with a _____ charge
- 1+
2.1-
How do you determine the ion charge of cations?
their ion charge equals A group number
ex: Na is in group 1A and forms Na^+
Ba is in group 2A and forms Ba^2+
For anions ion charge is equal to what?
their A group number minus 8
ex: S A group is 6A therefore, 6-8 = -1 –> S^2-
Main group monotamic ions have the same number of electrons as an _______________gas?
atom of the nearest noble
An ionic compound has zero net charge, why?
the positive charges of the cations balance the negative changes of the anions
Ion charges _______ appear in the compound formula?
do not
Oxoanion
anion in which an element usually a non metal is bonded to one or more oxygen atoms
With two oxyanions in the family Ions with more O atoms take the nonmetal root and the suffix ___________
-ate
With two oxyanions in the family Ions with fewer O atoms takes the non metal root and the suffix _______
-ite
With four oxyanions in the family, the ion with the most O atoms has the prefix ____, the nonmetal root, and the suffix _____
- per-
- -ate
With four oxyanions in the family, the ion with one fewer O atoms has just the root and the suffix _____
-ate
With four oxyanions in the family, the ion with two fewer O atoms has just the root and the suffix _____
-ite
With four oxyanions in the family, the ion with the least (three fewer) O atoms has the prefix ____and the suffix _____
- hypo-
- -ite
Hydrates
An ionic compound that has a specific number of water molecules in each formula unit
True or false water molecules refered to “waters of hydration” are apart of the hydrates structure
true
True or false heating can remove some or all of the hydrates water molecules leading to a different substance
true
how do you name and write an Acids formula?
We consider then as anions that have one or more hydrogen ions added to them to give a neutral compound
what are the two common types of acids ?
Binary acid and oxoacids
When do binary acid solutions form?
when certain gaseous solutions dissolve in water
Oxoacid names are similar to those of oxoanions, except for two suffix changes_________
-ate in the anion becomes -ic in the acid
-ite in the anion becomes -ous in the acid
oxyanion root + suffix -ic or -ous + separate word acid
what are the oxoanion prefixes?
hypo- and per-
Is the suffix hydro- used when naming oxoacids?
no
how are binary covalent compounds typically formed?
by the combination of two nonmetals
The element with the _________ number in the periodic table comes ________ in the name
- lower group
- first
The element with the _________ number comes _________ and is named with its root and suffix as _____
- higher group
- second
3.-ide
EXCEPTION: when the compound contains _____ and any other of the ________ the halogen name comes first
- oxygen
- halogens (chlorine bromine or iodine)
If both elements are in the same group the one with the higher ________ comes first
period number
covalent compounds use greek numerical prefixes to______
indicate the number of atoms of each element
The first element in the name of a covalent compound has a prefix only when ________
More than one atom is present
The second element usually has________
a prefix
Ex: What is the formula or carbon disulfide?
prefix di- means two the formula is CSsubscript2
EX2: What is the name of PCIsubscript 5?
P= phosphorous 5 chlorine atoms–> prefix penta-
phosphorous pentachloride
What are the simplest type of organic compounds? and what do they contain?
Hydrocarbons
only Carbon and Hydrogen
What is the simplest type of hydrocarbon?
Alkanes
What are the simplest types of Alkanes? and why?
Straight-chain alkanes because the carbon chains have no branches
How are alkanes named?
Named with a root based on the number of C atoms in the chain followed by the suffix, -ane
How do we calculate molecular mass?
sum of atomic masses
molecular mass = sum of atomic masses
Ionic compounds do not have molecules so the mass formula is sometimes called ________?
Formula mass
how do you calculate the formula mass of a compound with a polyatomic ion?
number of atoms inside parenthesis is multiplied by subscript number outside parenthesis
ex: Ba(NO3)2
atomic mass of Ba 2x atomic mass of N and 3 times atomic mass of O
Describe a molecular formula and what it does?
Uses elements symbols and numerical subscripts to give the actual number of atoms of each element in a molecule of the compound
what does the structural formula do?
Shows relative placement and connections of atoms in the molecule
