Ch. 2 The Chemical Context of Life Flashcards
how is emergent properties found in this ch?
It applies to the lowest level of biological organization-to the ordering of atoms into molecules and to the interactions of those molecules within cells.
Why can we use the terms “weight” and “mass” interchangeably on Earth?
The weight of an object is a measure of its mass (i.e. the heavier something is, the more mass it has, when we are in one location with constant gravity)
What are the four basic ingredients Greek philosophers proposed as the basis for all the variety of matter?
air, water, fire, earth
how many elements occur naturally, as we know now?
92
how many elements does life require?
25 of the 92 natural elements
what elements make up the majority of living matter, and how much?
CHNOPS=96%. A few other elements account for most of the remaining 4% of organism’s weight.
list the hierarchy of biological order
atom, molecule, organelle, cellular, tissue, organ, organ system, organism (a.m.o.c.t.o.o.o)
what are trace elements?
those required by an organism in only minute quantities
-some (ex. Fe) are needed by all, others are only needed by some species
What do the properties of chem elements and of the compounds they form, including the compounds crucial to life, result from ultimately?
the STRUCTURE of atoms
what is the unit of measurement for atoms and subatomic particles?
daltons (in honor of john Dalton, the br scientist who helped develop atomic theory around 1800) (same as amu-atomic mass unit)
mass of proton (which is roughly same as mass of neutron)?
close to 1 dalton (1.7 *10^-24 grams)
electron’s mass?
1/2000 that of neutron/proton-electron’s mass is ignored when computing total mass of atom
atomic number?
of protons, written as a subscript to left of symbol for element
mass #
written as superscript to left of an element’s symbol
most common carbon isotope?
c-12=99% of all carbon in nature
radioactive isotope?
nucleus decays spontaneously, giving off particles and energy.
used as tracers that follow atoms through metabolism, the chemical processes of an organism
what is energy?
ability to do work
potential energy?
- energy that matter stores bec/ of its position or location
- matter has tendncy to move to lowest possible state of potential energy
how does potential energy (P.E) relate to an e-‘s distance from the nucleus?
the more distant e-‘s are from positively charged nucleus, the more p energy they have
Electron Configuration and Chemical Properties?
first shell-no more than 2 e’s (s-spherical, 2 orbitals)
p-8 (dumbell, 3 orbitals)
each 2p orbital is positioned at right angles to the other 2
d-10
f-14
valence e’s or valence shell provides for chem behavior
inert=chemically unreactive
orbital
- 3D space that e’ is found 90% of the time
- e’s in different orbitals have nearly the same energy, but move in various volumes of space
