Unit 7 test Flashcards
What is the octet rule?
Atoms tend to gain, lose, or share electrons to achieve a full outer shell of eight electrons
The octet rule is a key concept in understanding chemical bonding and stability.
What are delocalized electrons?
Electrons that are not associated with a single atom or bond and can move freely within a structure, often described as a sea of electrons
This concept is important in explaining the conductivity and malleability of metals.
What is an ionic bond?
A type of chemical bond formed through the electrostatic attraction between oppositely charged ions
Ionic bonds typically form between metals and non-metals.
How is an ionic bond formed?
Through the transfer of electrons from one atom to another, resulting in the formation of cations and anions
This process usually occurs between a metal and a non-metal.
What is a covalent bond?
A type of chemical bond formed when two atoms share one or more pairs of electrons
Covalent bonds typically form between non-metal atoms.
How is a covalent bond formed?
Through the sharing of electron pairs between two atoms
This sharing allows both atoms to achieve a stable electron configuration.
What is a salt?
ionic compounds that do not start with H nor end with OH
Common table salt is sodium chloride (NaCl).
What does isoelectronic mean?
Having the same number of electrons or the same electronic structure as another atom or ion
Isoelectronic species often have similar chemical properties.
What is electrostatic force?
The attraction or repulsion between charged particles
This force is responsible for the formation of ionic bonds.
What is a cation?
A positively charged ion that has lost one or more electrons
Cations are typically formed from metals.
What is an anion?
A negatively charged ion that has gained one or more electrons
Anions are typically formed from non-metals.
What is a formula unit?
The smallest unit of an ionic compound
It represents the simplest form of the compound’s formula.
What is a molecule?
A group of two or more atoms bonded together by covalent bonds
Molecules can consist of the same or different elements.
What is an alloy?
A mixture of two or more metals, or a metal and another element
Alloys often exhibit enhanced properties compared to their component metals.
What is an amalgam?
An alloy of mercury with another metal
Amalgams are commonly used in dental fillings.
What are the two ways that atoms can achieve stability?
- Gaining, losing, or sharing electrons
- Achieving a full outer shell of electrons
These processes are fundamental for the formation of chemical bonds.
How can you determine the charge on an ion?
By considering the number of electrons lost or gained by an atom
The charge can be deduced from the atom’s position in the periodic table.
What are the properties of ionic compounds?
- High melting and boiling points
- Soluble in water
- Conduct electricity when dissolved or molten
These properties are due to strong ionic bonds and the ability of ions to move in solution.
How do you write formulas for ionic compounds?
By combining the symbols of the cation and anion, ensuring the total charge is neutral
The ratio of ions is determined by their charges.
How do metals bond and what properties do they have?
Metals bond through metallic bonds characterized by a sea of delocalized electrons, leading to properties such as malleability and conductivity
This bonding structure allows metals to conduct electricity and heat efficiently.
Which elements need Roman numerals in a name and why?
Elements that can form more than one type of ion, typically transition metals, need Roman numerals to indicate their charge
This ensures clarity about the specific ion being referred to in a compound.
