Essential Question: What are the differences and similarities among living things? Unit: Chemistry of Life, Chapter 2

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Essential Question What are the differences and
similarities among living things?Unit Chemistry
of Life, Chapter 2
Atom basic unit of matter, made of 3
subatomic particles (smaller than
atom) Proton positively charged
subatomic particle, found in nucleus, number of
protons mass number,
where it is found on periodic table Neutron
neutrally charged subatomic
particle, found in nucleus Nucleus
center of atom Electrons
negatively charges subatomic particle ex.
Carbon atom

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element made of 1 atom, pure
substance isotope atoms of same element
with different numbers of neutrons
ex. Carbon 12 6 protons, 6 neutrons, 6
electrons Carbon 13 6 protons, 7
neutrons, 6 electrons Carbon 14 6
protons, 8 neutrons, 6 electrons Radioactive
isotope nuclei unstable, breaks down over
time, scientists use for finding age of
rocks and fossils, kill and treat
cancer Compound substance formed by the
chemical combination of 2 or more
elements. Ex. H20, NaCl The physical
and chemical properties of compounds are usually
very different for the elements they are
formed from. Chemical bonds (2 types) 1) Ionic
bonds electrons transferred

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2) Covalent bonds electrons shared Ions
positively or
negatively charged atoms Molecule
result of covalent
bonding Summary What would a molecule
of water look like? Draw it with
chemical bonds-
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