unit 1 - bio chem Flashcards
chemistry
what r living things made off?
96% composed of 4 elements; C/N/O/H
Atomic Structure
all matter is composed of extremely small particles called atoms; smallest unit of any given element.
Subatomic Particles
1) core nucleus of protons and neutrons
2) electrons found in orbitals
(n0)
(p+)
(e-)
+weight of each subatomic particle
= neutral = 1.7 x 10-24g
= positive = 1.7 x 10-24g
=negative = 0
Isotope
a form of an element that differs in its # of neutrons
Radioactive Isotopes
by changing the number of neutrons, the chemical properties of the atom remain the same but the atom’s mass or stability of the nucleus is altered. which is used to determine the age of organic material/fossils + diagnoses in medician.
Ionic
1) between
2) mechanism
3) force of attraction
4) structure
1) metal and nonmetal
2) metal loses e- = cation
nonmetal gain e- = anion
3) electrostatic interaction (between + and -)
4) crystal lattice
Covalent
1) between
2) mechanism
3) force of attraction
4) structure
1) 2 or more non metals
2) valance e- r shared
3) physical shared
4) v depending on how mol interact w one another (polarity / size/ 3D shape)
intermolecular Forces
if a molecule is polar or large the force between diff mols plays an important role
Hydrogen - Bonds
strong polar bonds with electronegative elements like oxygen and nitrogen. Positivly charged hydrogen atoms will attract near by negative charges (INTRA between molecules)
Van Der Waal
INTER molecules between elements of a molecule. forces that they r extremely weak but work well in large mol, size, and shape. which influences the number of total strength.
Polarity
(electronegativity)
dont all act the same, therefore every element has its own characteristics of electronegativity. they are assigned values used to determine the overall pull of electrons. when an element has a greater pull on an e- it gaines a negative charge and if it holds a weaker pull will gain a positive charge.
Most electronegative
(diff when containing O/N vs C/H)
fluorine
1) they contain H/O/N/C elements
2) if they have O or N they are polar
3) C or H they will be nonpolar
water
makes up more then 65% of our body. we r polar due to shape which also forms hydrogen bond between one another
Properties of water
1)water is cling
2)absorbs lots of heat
3) solid water (ice)=less dence
4) very solvent
water clings
cohesion = water mol for h-bonds
adhesion = water form bonds w other polar substances
absorbs lots of heat
high SHC
moderates land and air temp
alows animal to thermo regulate
solid water = less dence
high density of 4c
ice flouts
prevents oceans from freezing
v solvent
charged end have a high affinity for charged ions and polar substances
1) polar
2) non polar
3) ionic
1) dissolved water = hydrophilic
2) does not dissolve water= hydrophobic
3) usually dissolved in water making aq solutions
acid and bases
not only dissolved in water but r partially dissociated into ions. if produced H+ ions it means they are acid or OH- is basic and can be neutralized by one another.
Reactions
1) dehydration
2) hydrolysis
3) neutralization
4) redox
dehydration
a chemical rxn in which a subunit of a large mol r joined by removing water
hydrolysis
water / cut
a chemical rxn in which water is used to split a large mol into small subunits
neutralization
a rxn in which an acid or base combine to make a salt and water
redox
Reduction / oxidation
= an electron transfer rxn
