Other Bonds
What does "like dissolves like" mean?
"Like dissolves like" is an expression used by chemists to remember how some solvents work. It refers to "polar" and "nonpolar" solvents and solutes. Basic example: Water is polar. Oil is nonpolar. Water will not dissolve oil. (POLAR WILL NOT DISSOLVE NONPOLAR)
Hydroxide (Explain what happens)
A hydrogen's protons get ripped off of H20, thus leaving behind the negative electron it contributed to the previous covalent bond. Therefore OH becomes an ion as well as a covalent bond, with a charge of -1
A line is...
A pair of electrons
Conductivity (Ionic)
Any ionic substance will become conductive in water, as the ions become mobile since the water splits apart the elements in the compound (NaCl in water)
C
C (Carbon and other other group 14 element) will have four bonds
Network Covalent Bonds
Covalent bonds in a web. This type of bonding is extra strong (stronger than ionic), has a high melting point, is hard. (Diamond C(s), quartz Si02, Silicon Carbide SiC)
Polyatomic Ions
Group of covalently bonded atoms with charge (Both covalent and ionic bonds) The relationship between two sections in covalent, while the other section is ionic
What is an easy way to remember the bonds elements have?
HONC
Feel+Example+Melting Point (Network Covalent)
Hard (Diamond/Graphite: C(solid), SiO2 (quartz), SiC (Silicon Carbide)), high
Feel+Example+Melting Point (Ionic)
Hard (NaCl, salt), high
H
Hydrogen (and any halogen) will have one bond
Types of Compounds
Ionic vs Molecular
Other word for network solids
Macromolecules
Why do metals conduct energy in terms of bonding?
Metals conduct energy, as they involve metallic bonding. Hence, this implies that a metal's electrons are mobile and can easily transfer
A molecule
Must only have covalent bonds!! Atoms that are bonded together and share electrons
N
N (Nitrogen and any other group 15 element) will have three bonds
Why does NaCl (s) not conduct, but NaCl (aq) does?
NaCl (s) does not have mobile ions, while NaCl (aq) has been split apart by the water the salt dissolved in and thus the ions can easily transfer. O has a higher EN than Cl and thus pulls it, calling NaCl to break. Note that you can also melt salt, but this takes longer
In order of strength (Strongest bonds to weakest bonds)
Network Covalent, Ionic, Metallic, Covalent
Types of Bonds
Network covalent bonds (made up of group 14, solids made out of vast networks of interconnected atoms), ionic bonds (bond between metallic + ion and nonmetallic - ion), metallic bonds (metals, mobile electrons), molecular/covalent bonds (sharing e-)
Conductivity (Molecular)
No!
Conductivity (Network Covalent)
No!
O
O (Oxygen and any other group 16 element) will have two bonds
Coordinate Covalent Bonds
Only one atom contributes both electrons in forming a covalent bond with another atom
The type of bond determined...
Physical characteristics of a substance
Line (Structural) Diagram
Replaces dots with lines (1 pair shared represented by 1 line)
Why does salt have a higher melting point than water?
Salt is an ionic bond, meaning that it is stronger than the covalent bond water. Therefore, more energy is required to split apart salt, due to the strong electrostatic force between its atoms.
Metalloids tend to...
Share (EN high, covalent)
Molecular Formula
Shows the elements and number of atoms in the formula (H2O)
Dot Diagram
Shows valence electrons and how shared using dots
Feel+Example+Melting Point (Covalent)
Soft (H2O), low
The most polar is the bond with...
The greatest difference in electronegativity
Metallic Bonding
The sharing of electrons between many atoms of metallic element. The metal atoms (think of golf balls) are positive ions in a sea of mobile electrons (the bathtub's water), therefore it is malleable/ductile since electrons act as a glue holding the positively charged nuclei together. This is how conductivity is explained, as electrons can easy transfer and are mobile and thus can move towards any attraction. The luster of metals can be explained by this, as since the electrons move around, they absorb light. THE ELECTRONS IN A METAL ARE SHARED AMONG ALL THE NUCLEI, SO THE ELECTRONS ARE NOT FIXED TO A SPECIFIC ATOM AND ARE MOBILE
Covalent Bonding
The sharing of electrons between two nonmetals. Note that for polar covalent, the element with the higher electronegativity is partially negative
Melting Point Rule
The stronger the bonds, the higher the melting point (more energy needed to break the bonds)
Polar and Nonpolar Covalent Bond
This only means that both bonds are present. For instance in a C2H6 bond, both nonpolar (between the two carbon atoms) and polar (between hydrogen and carbon) are present
Feel+Example+Melting Point (Metallic)
Varies Soft-->Hard (Na to Fe) (Copper), medium-->high
Conductivity (Metallic)
Yes (Always, as the electrons are mobile)
