The attractive force between two oppositely charged atoms and is the force with which an atom's nucleus attracts its electrons.
What is a Hydrogen bond?
A non-covalent molecular interaction resulting in an electrostatic bond formed between a positive H from one molecule and a negatively charged O or N from a neighboring molecule. Is responsible for water's lattice structure
Metabolis is:
The capture, storage and release of energy.
Give and example of a Synthesis Reaction
N + 3H => NH3
What is this an example of?
N+ 3H => NH3
Synthesis
Give an example of Decomposition
CH4 => C + 4H
CH4 => C + 4H is an example of which reaction?
Decomposition
Give an example of an exchange reaction
HCl + NaOH => NaCl + H2O
HCl + NaOH => NaCl + H2O is an example of
Exchange reactions
Example of Reversible Reaction
H2O + CO2 <=> H2CO3
What do enzymes do?
Reduce energy of activation without being permanently changed or used up
Role of Water in Biological Processes:
provides a fluid environment that allows molecular mobility
Water's unusual properties
solubility
reactivity
high heat capacity
lubrication
Viscosity is defined as:
the thickness of a liquid created by its molecular interaction. Creates friction and increases resistance to flow.
Surface tension of water results from
the cohesiveness of the interlocking hydrogen bond structure
The high dielectric constant results from
the dipole character of the molecule, which reduces the electrostatic forces between other charged particles
Water's intracellular and extracellular solvent ability is due primarily to which two properties of water?
tendency to form hydrogen bonds
dipolar character
Aliphatic molecules are
hydrocarbon chains (typically fatty acids)
An amphiphatice molecule is one that
has a charge on one side and no charge on the other side
Micelles
the polar heads of the phospholipid molecules are surrounded by water.
Amphiphatic molecules make up
micelles and bilayer membranes
Solution
a solvent that has disolved a solute
Molarity
# of moles/ liter of solvent
molality
number of moles/ kg of solvent
Normality
gram equivalent of solute/ liter of solvent
Definition of an acid
a substance that dissociates into one or more Hydrogen ions (H+) and one or more anions. Proton donor
Definition of a base
A substance that dissociates into one or more OH- ions and one or more cations. proton acceptor
Strong acids and Strong bases react to produce
Water and Salt
Water and Salt are the products of a reaction between
a strong acid and a strong base
[HA] <=> [H+] [A-]
What happens if an acid stronger than HA is added to the solution? What happens if a base is added to the solution?
the equilibrium is shifted to the left in favor of association
the equilibrium is shifted to the right in favor of dissociation and the formation of H+.
Keq=
[concentration of the products]/[concentration of the reactants]
[concentration of the products]/[concentration of the reactants]
formula for K equilibrium constant
Keq of water =
1.8 x 10-16
pH represents:
the amount of free H+ ions present in solution
pK represents
the amount of ionization product at equilibrium
Hendersen-Hasselbach equation
pH= pK + log ([A-]/[HA])
Why does water freeze from the top down?
Water freeze from top to bottom as its top layer is exposed to cold
air.
Also, water have a high heat capacity, so the temperature inside a
considerable depth is high.
The layer expose to air loose its temperature and freeze, while the inner layer remains hot.
How does the lattice design of ice differ fromt hat of liquid water?
Water's latice structure is open where as ice has a closed latice
Why does ice expand?
because of its rigid OH verctors that is created when a water molecule interacts with four other water molecules