Chem - Lecture 4 Flashcards
• Why aren’t the metalloids in a group (column)?
- Diagonal relationship
a) Likely hood to form a ______ increases down and to the left
• Why aren’t the metalloids in a group (column)?
- Diagonal relationship
a) Likely hood to form a cation increases down and to the left
Representing Molecules
• Molecular formula
– Indicates the actual number of ______ in a molecule
• E.g. H2O, C6H12O6 (glucose), C2H6
– Common for ______ compounds
Representing Molecules
• Molecular formula
– Indicates the actual number of atoms in a molecule
• E.g. H2O, C6H12O6 (glucose), C2H6
– Common for covalent compounds
Representing Molecules
• Empirical formula
– Indicates relative number of ______
– Subscripts represent the lowest possible ______- ______ ratios
• E.g. NaCl, Fe2O3, C6H12O6 → CH2O, C2H6 → CH3
– Common for ____ compounds
Representing Molecules
• Empirical formula
– Indicates relative number of atoms
– Subscripts represent the lowest possible whole-number ratios
• E.g. NaCl, Fe2O3, C6H12O6 → CH2O, C2H6 → CH3
– Common for ionic compounds
Representing Molecules
• Structural representations
– Shows how atoms are ______
– Some version also show the 3D orientation of ______ in the molecule
• Examples shown on right: H2O, C2H6, SF6
• Structural representations
– Shows how atoms are connected
– Some version also show the 3D orientation of atoms in the molecule
• Examples shown on right: H2O, C2H6, SF6
Ionic Naming
• Cations
- Determine if the metal can form more than one ______ a) If the metal has only ______charge: use ______ name
b) If the metal can more than ______ charge: indicate the ______ of ______ in parenthesis using Roman numerals - ______ cations, add –ium suffix • Example: NH3 is ammonia →NH4+ is ammonium
Ionic Naming
• Cations
- Determine if the metal can form more than one charge
a) If the metal has only one charge: use element name
b) If the metal can more than one charge: indicate the magnitude of charge in parenthesis using Roman numerals - Nonmetal cations, add –ium suffix • Example: NH3 is ammonia →NH4+ is ammonium
Ionic Naming
• Anions
1. _______ anions: replace suffix with -ide
• Cl which is chlorine becomes Cl- which is ______
• N which is nitrogen becomes N3- which is ______
- ______ (polyatomic anions) • See table 3.4 for a more comprehensive list
Ionic Naming
• Anions
1. Monatomic anions: replace suffix with -ide
• Cl which is chlorine becomes Cl- which is chloride • N which is nitrogen becomes N3- which is nitride
- Oxyanions (polyatomic anions) • See table 3.4 for a more comprehensive list
Oxyanions
- When there are just two oxyanions for a given element
- ______ anion: –ate suffix
- ______ anion: –ite suffix
- Both the larger and smaller anions will have the same charge
Oxyanions
- When there are just two oxyanions for a given element
- Larger anion: –ate suffix
- Smaller anion: –ite suffix
- Both the larger and smaller anions will have the same charge
– Boron, Carbon, Nitrogen
• These three atoms are too _____ to accommodate more than three oxygens
» BO33- → _______
» CO32- → _______
» NO3- → _______ & NO2-→ _______
– Note how their charges _______ by one as you go left-to-right on the periodic table
– Boron, Carbon, Nitrogen
• These three atoms are too small to accommodate more than three oxygens
» BO33- → borate
» CO32- → carbonate
» NO3- → nitrate & NO2-→ nitrite
– Note how their charges decrease by one as you go left-to-right on the periodic table
– Phosphorous, Sulfur, Chlorine
• These three atoms are _______ enough to accommodate 4 oxygens (and chlorine forms four separate oxyanions)
» PO43- → _______ & PO33- → _______
» SO42- → _______ & SO32- → _______
» ClO4-→ _______ & ClO3- → _______ & ClO2-→ _______
ClO-→ _______
– Note how their charges decrease by one as you go ___-_-___
– Phosphorous, Sulfur, Chlorine
• These three atoms are large enough to accommodate 4 oxygens (and chlorine forms four separate oxyanions)
» PO43- → phosphate & PO33- → phosphite
» SO42- → sulfate & SO32- → sulfite
» ClO4-→ perchlorate & ClO3- → chlorate & ClO2-→ chlorite ClO-→ hypochlorite
– Note how their charges decrease by one as you go left-to-right
Naming Acids
• Acids are compounds that yield H+ in water
– This is one of several definitions of an acid
» Most common definition
Naming Acids
• Acids are _______ that yield H+ in water
– This is one of several definitions of an acid
» Most common definition
- Anions with the –ide suffix form acids with the _______ prefix and –ic suffix
- Br- (bromide) → HBr (_____brom__ acid)
- F- (fluoride) → HF (hydro_____ic acid)
- Anions with the –ide suffix form acids with the hydro prefix and –ic suffix
- Br- (bromide) → HBr (hydrobromic acid)
- F- (fluoride) → HF (hydrofluoric acid)
- Ions with the –___ suffix become: -ic acid
- NO3- (_____) → HNO3 (nitric acid)
- SO42- (_____) → H2SO4 (sulfuric acid)
- CH3CO2- (_____) → HCH3CO2+ (acetic acid)
- Ions with the –ate suffix become: -ic acid
- NO3- (nitrate) → HNO3 (nitric acid)
- SO42- (sulfate) → H2SO4 (sulfuric acid)
- CH3CO2- (acetate) → HCH3CO2+ (acetic acid)
- Ions with the –___ suffix become: -ous acid
- NO2- (_____) → HNO2 (nitrous acid)
- SO32- (_____) → H2SO3 (sulfurous acid)
- Ions with the –ite suffix become: -ous acid
- NO2- (nitrite) → HNO2 (nitrous acid)
- SO32- (sulfite) → H2SO3 (sulfurous acid)
Elemental Diatomics
- There are _____ molecules that naturally occur as diatomic molecules
- Gasous: H2, N2, O2, F2, Cl2
- Liquid: Br2
- Solid: I2
– e.g. “nitrogen gas”
• N2
– e.g. “solid iodine”
• I2
Elemental Diatomics
- There are seven molecules that naturally occur as diatomic molecules
- Gasous: H2, N2, O2, F2, Cl2
- Liquid: Br2
- Solid: I2
– e.g. “nitrogen gas”
• N2
– e.g. “solid iodine”
• I2
Binary Molecular Compounds
• Compounds containing two _____
1. List the element furthest _____ (_____ group) first
– Exceptions
» Compounds that contain a _____Cl, Br, I) and oxygen
• In these cases oxygen is listed last
» Organic compounds often list carbon first, then hydrogen
• CH4, C6H6 – e.g. CO2, N2O
2. Elements in the same group, list the _____ atomic number first – e.g. SO2
3. The second element is given the suffix –ide
- Greek prefixes denote _____ of atoms in molecule
Binary Molecular Compounds
• Compounds containing two nonmetals
1. List the element furthest left (lowest group) first
– Exceptions
» Compounds that contain a halogen (Cl, Br, I) and oxygen
• In these cases oxygen is listed last
» Organic compounds often list carbon first, then hydrogen
• CH4, C6H6 – e.g. CO2, N2O
2. Elements in the same group, list the highest atomic number first – e.g. SO2
3. The second eleme
nt is given the suffix –ide
- Greek prefixes denote number of atoms in
