Units 22-23 Flashcards
Ionic compound
A compound formed between a metal and a non-metal.
Crystalline solids at room temperature. Conduct electricity when molten or dissolved in water.
What is another name for ionic compounds?
Salts
Ionic bonding
The bonding in ionic compounds.
Why do ionic bonds have such high melting points?
Metal atoms lose electrons and become positive ions. Non-metal atoms gain electrons and become negative ions. Positives surround negatives and vice versa.
So each ion is experiencing attractive interactions with many ions of the other type.
True or False: All salts are brittle and cannot be easily reshaped.
True
True or False: Salts are ionic conductors
True
What is an ionic conductor?
Solids don’t conduct electricity, but salts dissolved in liquids DO.
True or False: Non-metal atoms want to keep their electrons so much they sometimes steal electrons from other atoms.
True
True or False: The bonding between ionic compounds and metal compounds is similar
False
Do metals or non-metals more easily gain electrons?
metals
Do metals or non-metals more easily LOSE electrons?
non-metals
True or False: In ionic bonding, metals and non-metals combine in a way that one atom completely gives and one atom completely receives, forming IONS (positive and negative).
True
True or False: Ionic bonds allow electrons to flow between multiple atoms freely.
False
Why are ionic bonds so strong if the electrons are bound to orbitals surrounding a specific atom?
Because of the electrostatic force/attraction between the many created positive and negative ions resulting from the bond.
Each atom is attracted to forces many atoms away from it, at great distances, as well as all those that are close. So they are all linked together like a spiderweb.
Kind of like World of Goo bonds between many atoms
How are ionic bonds shielded from the repulsive forces of their own positive/negative attractions?
Because each positive ion is surrounded by negative ions, and vice versa. This shields them from the repulsive forces and allows them to create many bonds.
True or False: Ionic bonds will always form in a way that leaves the compound electrically neutral
True
True or False: In ionic bonds, the negative and positive charges are equal, even though sometimes it takes more atoms of one type to achieve this.
True
True or False: Electrostatic forces are long range
True
Why do ionic bonds have high melting temperatures?
Because it takes a great deal of thermal energy to pull individual ions away from their many connected neighbors
Why do ionic compounds break so easily? Why are they brittle?
Because in order to flatten, bend, or change the shape of a compound, layers of atoms must slide over each other (in all matter).
But in ionic compounds, having a layer of atoms move over a bit, puts positive ions in direct contact with other positives, and negatives in contact with negatives. This creates strong repulsive forces that push the layers apart.
Electrolyte
A chemical compound that ionizes when dissolved in water to produce an electrically conductive medium.
True or False: Gatorade is a good electrical conductor
True
Why don’t solid salts conduct electricity?
Because electricity is conducted through flowing/moving electrons. But in ionic bonds, electrons are stuck in place. They can’t move, so electricity doesn’t flow.
Why can liquid salts conduct electricity?
When the solid melts, the electrons become free to move.
Why are salts usually transparent?
Because electrons are bound to specific discrete energy levels, they are not free to roam around. And it takes a higher energy than a photon of visible light to excite an electron to a higher energy level. UV or above.
The light energy does not excite the electrons, so they do not move to higher levels and become absorbed (emitting energy). They just pass through
What light range provides enough energy to cause salts to be opaque or colorful?
UV or higher
Why do salts appear white or cloudy?
Because of all the many cracks that are reflecting light (not absorbing visible light).
True or False: The metal and nonmetal atoms in ionic compounds form ions with the noble gas configuration
True
Octet rule
An atom will most likely form an ion that has the ns^2np^6 configuration of the closest noble gas atom.
What properties of salts change as a result of the ionic charge on transition metal ions?
Color and magnetism
Do ionic liquids conduct electricity as well as metals?
Nope
Do metals or nonmetals have large atoms?
Metals
Do metals or nonmetals have many valence electrons?
Nonmetals
Do metals or nonmetals have few valence electrons?
Metals