Chapter 2 BIO 1200
polar covalent bond
A covalent bond in which electrons are not shared equally
Isotope
Atoms of the same element that have different numbers of neutrons
covalent bonds
Bonds created by sharing electrons with other atoms.
ionic bond
Formed when one or more electrons are transferred from one atom to another
When water ionizes, it produces what ions? Select all that apply.
OH- H+
octet rule
States that atoms lose, gain or share electrons in order to acquire a full set of eight valence electrons
Energy is defined as
The capacity to do work.
What part of an amphipathic molecule would be oriented toward the center of a micelle?
The nonpolar region
In a micelle, which portion of the amphipathic molecules are oriented toward the surface of the sphere?
The polar region
Hydrophobic
Water fearing
The hydrogen bonds between water molecules form between:
an oxygen atom on one water molecule and a hydrogen atom on a second water molecule
Electronegativity is the ability of an atom to:
attract electrons
Hydrolysis reactions:
break apart molecules via water
Properties of water
cohesion, adhesion, excellent solvent, solid is less dense than liquid, specific heat
Acids
compounds that form hydrogen ions when dissolved in water
Atoms share a pair of electrons when they form a(n) bond
covalent
A covalent bond is one in which a pair of electrons:
is shared between two atoms
To freeze water, energy is:
released
The concentration of a liquid is defined as the amount of ______ dissolved in a unit volume of solution.
solute
hydrogen bonding
the intermolecular force in which a hydrogen atom that is bonded to a highly electronegative atom is attracted to an unshared pair of electrons of an electronegative atom in a nearby molecule
chemical reactions
the making and breaking of chemical bonds, leading to changes in the composition of matter
An atom's atomic number represents:
the number of protons
Hydrophilic
water loving
Bases
Compounds that reduce the concentration of hydrogen ions in a solution.
nonpolar covalent bond
a covalent bond in which the electrons are shared equally by the two atoms
Molecules with covalent bonds:
are flexible within certain limits
The of an atom is a measure of its ability to attract electrons when in a bond with another atom.
electronegativity
Atoms are most stable when their outer shells are filled with
electrons.
Compared with liquid water, ice has
greater hydrogen bonds between individual water molecules a more orderly arrangement of water molecules
In a(n) reaction, water is used to break apart another molecule.
hydrolysis
Within an atom's structure, electrons can be found:
in cloudlike orbitals
atomic mass scale
indicates an atom's mass relative to the mass of other atoms
Ionic bond list
non metal to metal total transfer of electrons high melting and boiling points solid soluble in water positive and negative charge
Atoms are most stable when:
their outer shells are filled
Buffers
weak acids or bases that can react with strong acids or bases to prevent sharp, sudden changes in pH
hydrogen bond
weak attraction between a hydrogen atom and another atom
Which of the following changes in the physical state of water require the input of energy?
Changing from liquid to gas Changing from solid to liquid
When water is heated, the rate at which bonds break increases, and water molecules are converted to the state.
Hydrogen gas
Atoms share a pair of electrons when they form a(n) bond.
covalent
amphipathic
having both a hydrophilic region and a hydrophobic region
When two water molecules are near each other, a hydrogen bond will form between the more positive and the more negative atoms of neighboring water molecules.
hydrogen oxygen
Which state of water is the most dense?
liquid
Importance of water
most abundant compound in body, critical in all physiologic processes, deficiency (dehydration) threatens health, universal solvent, stable liquid at ordinary temperatures & participates in body's chemical reactions
Isotopes of the same element differ in their number of:
neutrons
Covalent bond list
non metal to non metal sharing electrons low melting and boiling points no charges depends on polarity for solubility and charges
The region within an atom that surrounds the nucleus and in which there is a high probability of finding an electron is called a(n)
orbital
Unpaired , Correct Unavailable electrons enable chemical bonds to form among atoms.
valence
When water freezes:
water molecules are packed into a less dense formation the rate of hydrogen bond breakage slows the H2O molecules in ice are in a much more orderly arrangement than in the liquid state