Unit 4-6 Flashcards
What is the goal of bonding?
For an atom to become more stable
Molecules are _____ compounds.
Covalent
Physical characteristics of ionic compounds (trends):
Very high melting and boiling points, good conductors of heat and electricity, and many ionic compounds are soluble in water and an electrolyte: conducts electricity when interacting with water
_____ compounds contain metals and nonmetals
Ionic
_____ compounds contain all nonmetals
Covalent
When naming compounds, prefixes are for _____ compounds
Covalent (only)
When an atom becomes an ion it’s _____ changes.
Electronic configuration
List the metal elements with fixed ionic charges:
Groups 1 and 2, period 2-6.
Al^3+, Ga^3+, Zn^2+, Cd^2+, Ag+
Nonmetal anions all have _____ charges.
Fixed
_____ determine(s) chemical properties and physical properties of an element.
Valence electrons
_____ change number of electrons.
Ions
_____ change number of neutrons.
Isotopes
All ionic compounds must have an overall charge of _____.
0
Is the cation or anion written first in a formula?
Cation
Roman numerals are used for elements without _____.
Fixed charges
_____ are the only two positively charged ions.
Polyatomic cations (hydronium and ammonium)
Covalent compounds _____ electrons
Share
Ionic compounds _____ ions.
Steal
Molecular geometry is based on the _____ between pairs of electrons.
Repulsion
The most stable arrangement for a Lewis structure is with pairs of electrons (bonds or lone pairs) _____ each other.
Farthest from
In a Lewis structure, if there are no lone pairs around a central atom, and there are only two atoms, the bond is _____.
Linear
3 atoms and one lone pair create what shape around an atom in a Lewis structure?
Trigonal pyramidal (107 degree angle)
2 atoms and 2 lone pairs create what kind of shape around an atom in a Lewis structure?
Bent shape (105 degree angle)
4 atoms and 0 lone pairs create what shape around an atom in a Lewis structure?
Tetrahedral (109.5 degree angle)
The polarity of _____ affects physical and chemical properties.
Molecules! (This is called electronegativity)
Electronegativity defines the attraction between _____ and _____.
Atoms and electrons
Electronegativity has an attraction measure of _____.
0.0-4.0
Atoms bound to themselves have ___ electronegativity attraction.
0
List the bond type and it’s measure:
= or near = sharing of electrons.
Nonpolar covalent (0.0-0.4)
List the bond type and it’s measure:
Unequal sharing of electrons
Polar covalent (0.5-1.5)
List the bond type and it’s measure:
Ionic IF it’s a metal
Polar IF it’s a nonmetal
Ionic or polar covalent (1.6-2.0)
List the bond type and it’s measure:
Very unequal sharing of electrons
Ionic (2.1-4.0)
3 atoms bound to a central atom with 0 lone pairs forms a _____
Triagonal planer shape
0-0.4 is what bond type?
Nonpolar covalent
.5-1.5 is what type of bond?
Polar covalent
1-6-2.0 is what type of bond?
Ionic OR polar covalent depending on if metals are involved.
2.1-4.0 is what type of bond?
Ionic!
The polarity of a molecule is determined by _____.
Shape
Avogadro’s number is:
6.022 x 10^23 particles / 1 mol
Amu = x / x
1.66 x 10^-27
Any time you convert •element to element •element to compound •compound to compound You must use \_\_\_\_\_.
Molar ratios
A mole refers to 6.022 x 10^23 _____, _____, or _____.
Atoms, molecules, particles, or ions
Molar mass is in units of:
G/1 mol
Breaking and forming bonds are associated with what type of reaction?
Chemical
Only physical means are needed to separate _____ _____.
Ionic compounds
Breaking _____ _____ requires a chemical reaction.
Covalent bonds
12 g carbon contains how many particles?
6.022 x 10^23
Oxidation _____ electrons
Loses (becomes +)
Reduction _____ electrons.
Gains (becomes -)
List characteristics of covalent bonds:
Low boiling and melting point, poor conductors of heat and electricity
Percent yield is:
Experimental (actual) yield/ theoretical yield= x multiplied by 100
