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Earth and Physical Science
what are waves of radiation that are characterized by electric and magnetic fields?
7 electromagnetic waves (short to long)
the visible part of the spectrum is further subdivided by what?
7 visible forms of electromagnetic waves (long to short)
2 units that energy is often quantified
which is larger b/w Joules and calories?
what is the term for the amount of energy associated with an object's motion; energy of motion?
kinetic energy (KE)
any increase in an objects velocity results in a dramatic increase in what?
the object's KE
any doubling of the velocity will cause the KE to increase by a factor of what?
what is the term for the amount of energy stored in an object; stored energy?
potential energy (PE)
what is the formula for KE?
what is the formula for PE?
what can be used to produce an object's motion?
what is the term for when energy is not lost but rather transferred back and forth between KE and PE?
law of conservation of energy
what is the term for anything that takes up space and has mass?
mass is not the same as what?
what is the quantity of matter an object has?
what are substances that cannot be broken into simpler types of matter?
what are positively charged subatomic particles found in the nucleus of an atom?
the number of protons in an atoms distinguishes what?
the atomic number of the element.
what are neutral subatomic particles found in the nucleus of an atom?
what are negatively charged subatomic particles found in various energy levels (orbital shells)?
what is a dynamic event that alters the chemical makeup of an atom?
what may cause imbalance in charge, resulting in either excessive protons or neutrons?
what is an imbalance that produces a positively or negatively charged atom?
what two main things contribute to an atoms mass?
what is the term for the total number of protons and neutrons found within a nucleus of an atom?
what is the average mass of all of the known isotopes of an element?
3 things that contribute to the atoms mass
what is the term that refer's to the positive or negative distribution within an atom?
what are atoms with the same number of protons, but different number of neutrons?
what controls the rate of chemical reactions?
what increases reaction rates?
what reduced reaction rates?
reaction rates depend on what?
the frequency of contact of reactants with catalysts
increasing reaction rates may be accomplished artificially by increasing what?
how does catalysts increase reaction rates?
by lowering the activation energy
elements used to be arranged by what?
how are elements now arranged in the periodic table?
by atomic number
what its he arrangement of electrons within orbits around the nucleus?
the number of electrons increase from _____ to ____?
left to right
as the number of protons increase, what happens to the nuclear charge?
as protons and nuclear charge increase what happens to the atomic radii?
moving down a group or column, what happens to the number of electrons and filled electron shells?
as the number of electrons and filled electron shells increase moving down a column, what happens to the valence electrons?
remain the same
what are the electrons i the outermost shell of an atom?
what happens to the electrons as the number of filled energy shells increase?
electrons become farther away from the nucleus
what happens to the atomic radii as the electrons become farther away from the nucleus?
what happens to ionization energy as the atomic radii increases moving down a group?
the energy decreases
what is the measure of an atom's attraction on electrons in a chemical bond?
the greater the electronegativity the greater the what?
the attraction for bonding electrons
what is the term from the chemical merging of atoms due to their electron arrangement?
what are elements that donate highly conductive electrons to their environment?
what is a protein that is soluble?
each amino acid sequence produces what kind of structure?
a 3-D structure
3 external factors that effect the activity of an enzyme?
what is the value that measure the H+ concentration within a solution?
what is a molecular surface acted upon by an enzyme?
what are chemical reactions with a cell?
enzymes attaches to substrates molecules and convert the molecules into what?
flexibility of an enzyme allows its active site surface to do what when placed in contact with a substrate
what acts to lower the activation energy?
what happens to the barrier between the products and the reactant when enzymes lower the active energy?
the barrier is lessened
when the barrier between products and reactant are lessened by an enzyme, it allows what to occur?
a greater reaction rate
what can compete with substrates by blocking its active sites?
enzymes can catalyzed what 2 reactions?
CO2 + H2O <-->H2CO3<-->H+ + HCO3
what is used to measure the strength of acidic/basic solutions?
what is a solution with a pH value less than 7?
what is a solution with a pH value greater than 7?
2 methods of chemical bonding
what is the electrical attraction between ions of opposite charged?
what is the sharing of electrons between atoms?
3 examples of hydrocarbons
2 subdivision of hydrocarbons
saturated hydrocarbons are also known as what?
saturated hydrocarbons are composed entirely of what kind of bonds?
saturated hydrocarbon's carbons are fully connected with what element?
what is the general formula for saturated hydrocarbons?
what are the basis of petroleum fuels?
how many bonds are in unsaturated hydrocarbons?
one or more double or triple bonds b/w carbon atoms
what are unsaturated hydrocarbons with 1 double bond?
what is the general formula of alkenes?
what are unsaturated hydrocarbons with triple bonds?
what is the generals formula of alkynes?
metals are to the ____ of the zig zag line of the periodic table?
nonmetals are to the _____ of the zig zag line of the periodic table
what is in contact with the zig zag line?
what are elements that may accept or donate electrons and possess a mixture of metallic and nonmetallic properties?
what tends to be a cation?
what tends to be an anion?
what kind of bonds complete on another by donation and acceptance of electrons?
what kind of bond share electrons between atoms?
what electrons are shared in covalent bonds?
covalent bonding is greatest between atoms what share similar what?
electronegativites; or similar attractions for electrons.
electronegativity tends to increase from ___ to right___ on the periodic table?
left to right
covalent bonding results between atoms on what side of the table?
same side of the table
what is a visual representation for covalent bonding b/w atoms of a molecule?
reactions must be balanced according to what 2 things?
what is the goal of balancing an equation?
to make certain that there are equal numbers of each atom on the reactant side and the product side
subscripts of an element represent what?
the number of atoms of that element
oxidation involves what?
reduction involves what?
3 examples of oxidation-reduction reactions
what refers to the chemical reactions in living organisms that are necessary to maintain life?
acid+ + base- -->____ +_____
salt + water
water is considered what?
what is a molecule that posses both positive and negative atomic structure?
what is the term that can chemically split the liquid water molecule into gaseous components?
what serves as a pH standard?
pure water that serves as a pH standard is central to what 2 things?
2) enzyme function
pure water has a low what?
what is the maximum density of water?
what is the ratio of mass/volume?
what is the melting point of ice?
what is the boiling point of liquid water?
the boiling point of water depends on what?
what is alternatively used to express temperature?
what is a metric temperature scaled defined by an absolute zero reference point?
what is the term for the temperature and pressure at which water will coexists as a solid, liquid, and gas?
triple-point of water
Kelvin temperatures are standardized by what?
the triple-point of water
what is the energy required to raise one unit of mass by a substance by 1℃?
water possess the ____ highest specific heat?
large specific heat of water enables it to undergo what?
minor temperature changes compared to the environment
water also has a high heat of what?
what is the amount of heat necessary to cause a phase transition b/w a liquid and gas?
heat of vaporization
water acts as the universal what?
what theory states that atoms (or molecules) are always in constant motion?
what state is considered to have a fixed shape and volume?
what is the term in which the atoms are arranged in a highly ordered state, to state in which the atoms lack true order?
solids are often considered to exist at high ___ and low ___?
liquid states have a ____ volume and changing ____?
what is the term for the physical connection b/w atoms that does not alter the chemical nature of the atoms?
liquids will spread out over a ____ volume?
gaseous states have a changing ____ and ____
what is the term that is related to the energy needed to cause phase transition at fixed temperature?
more energy is needed to transition from a ____ to ___?
liquid; gas (opposed to liquid to solid)
transitions b/w solid, liquid, and gas phases are achieved by how?
adding or subtracting energy from the system
what is the flow of energy due to the difference in temperature?
the liquid to gas transition is through what 2 things?
liquid to gas transition requires the addition of what?
the gas to liquid transition is achieved by what?
gas to liquid requires what?
a subtraction of heat
evaporation of a liquid is achieved by what 3 things?
3)fast movement of the surrounding air mass
evaporization occurs by the physical collision at the surface of what?
surface layer of a liquid
the physical collision at the surface layer of the a liquid acts to remove what?
the faster-moving liquid molecules
vaporization occurs through the phase transition from ____ to ___?
liquid to gas
what is the alternation of the physical state b/w liquid, solid, gas?
transition from a liquid to a gas takes place by breaking what?
the physical bond within the liquid.
heat of vaporization to transition from a liquid to a gas depends on what 2 things?
what occurs through phase transition from a gas to a liquid?
condensation takes place by creating what?
physical bonds within the gas.
what is the formula for heat of vaporization?
H=M(g) x L(cal/g)
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