02 - Bonds and Polarity Flashcards
Ionic bond
the attraction between 2 oppositely charged ions
Covalent bond
the sharing of a pair of valence electrons by two atoms
Hydrogen bond
Is an attraction between a hydrogen atom carrying a partial positive charge, and an electron carrying a partial negative charge
Bonding capacity
Corresponding to the number of covalent bonds the atom can form
Electronegativity
The attraction of a particular atom for the electrons of a covalent bond
Polar
Overall charge is unevenly distributed, hydrophilic
Nonpolar
refers to molecules or parts of molecules that do not have regions with distinct electrical charges, typically hydrophobic
Nonpolar covalent bonds
In a covalent bond between two atoms of the same element, electrons are equally shared because the 2 atoms have the same electronegativity
Hydrophobic
Substances that are non-ionic and non-polar, repel water
Hydrophilic
Water- loving, any substance that has an affinity for water
Solvent
The dissolving agent of a solution
Solute
substance that is dissolved
Hydration shell
Sphere of water molecules around each dissolved ion
Dissolution
The process where a solute in a gaseous, liquid, or solid phase dissolves in a solvent to form a solution
Solubility
Degree to which a substance dissolves in a solvent to make a solution
What are three important chemical bonds?
Ionic, covalent, and hydrogen
What do ionic bonds form?
When ions bind together, they tend to form crystal structures called ionic compounds, not molecules
What is an example of an ionic compound?
Sodium chloride (CL)
What do covalent bonds form?
Molecules
What creates a polar covalent bond?
Unequal electronegativity creates a polar covalent bond
What bonds are an example of nonpolar bonds?
Hydrogen, shares electrons equally
Oxygen, shares electrons equally
What covalent bond is an example of polar?
Water, slightly polar because electron spends more time near Oxygen and less time near it
What are hydrogen bonds?
Hydrogen bonds are a type of weak chemical bond that occurs when a hydrogen atom, which is already bonded to a highly electronegative atom like oxygen, nitrogen, or fluorine, is attracted to another electronegative atom from a different molecule or a different part of the same molecule
What is the most common mechanism in changing the acidity of a solution?
Add or remove protons or hydrogen ions
In biological systems, what are acids?
Acids are substances that can donate hydrogen ions (H⁺) when dissolved in water. Acids lose extra proteins.
In biological systems, what are bases?
Bases are substances that can accept hydrogen ions (H⁺) or release hydroxide ions (OH⁻) when dissolved in water. Bases pick up extra proteins.
