beth final
a substance absorbs heat energy by the process of
ALL OF THE ABOVE conduction convection radiation
chemistry is the study of
ALL OF THE ABOVE matter transformations of matter the submicroscopic realm
substances are composed of tiny particles. temperature is related mostly to the particles
average kinetic energy
temperature is generally proportional to a substances
average translational kinetic energy
microscopic ice slush in a glass of water tends to make the entire slush-water
less dense
metals are both good heat and electrical conductors due to
looseness of outer electrons in metal atoms
a substance that heats up relatively quickly has a
low specific heat capacity
the fact that desert sand is very hot in the day and very cold at night is evidence that sand has a
low specific heat capacity
the bohr model is similar to a
miniature solar system
whether one object is warmer than another object has most to do with
molecular kinetic energy
if an iron nucleus split into two, its fission fragments would hsve
more mass per nucleon
which of the following is electrically neutral?
neutron
is it at all possible for a hydrogen nucleus to emit an alpha particle?
no because it does not contain enough nucleons
if you have a molecule of TiO2, how many molecules of 02 does it contain?
none, 02 is a different molecule from TiO2
the atomic mass number of an element is the same as the number of its
nucleons
elements in the periodic table are listed in order of atomic
number
how many electrons are there in the third shell of sodium, Na?
one
the half life of an isotope is one day. at the end of 2 days the amount that remains is
one quarter
in an electrically neutral atom, the number of protons in the nucleus is balanced by an equal number of
orbital electrons
if two protons and two neutrons are removed from the nucleus of neon-20, a nucleus of which element remains?
oxygen-16
a fire walker walking barefoot across hot wooden coals depends on woods
poor conduction
a good heat conductor is a
poor insulator
different isotopes of the same elements have different numbers of
protons
the atomic number of an element is the same number as the number of its
protons
the weight of matter comes mostly from
protons and neutrons
which is the smallest particle listed? molecule atom neutron proton quark
quark
the process of making helium from hydrogen is an example of
radioactivity
a bimetallic strip used in thermostats relies on the fact that different metals have different
rates of thermal expansion
a high temperature source radiates relatively
short wavelengths
a friend produces a Geiger counter to check the local background radiation. it ticks. another friend, who normally fears most that which is understood least, makes an effort to keep away from the region of the Geiger counter and looks to you for advice. what do you say?
the Geiger counter is detecting naturally occurring background radiation
the decision to wear dark clothing during winter months is wise because
dark colors absorb heat
when a uranium nucleus emits and alpha particle, the atomic number of the new element is
decreased by 2
as a hot iron ring cools the diameter of the hole
decreases
the volume of matter comes mostly from its
electrons
your toes feel warmer on a rug than on a tile floor because the rug
is a better insulator than tile
a sample of radioactive material is usually a little warmer than its surroundings because
it's atoms are continually being struck by alpha and beta particles
which has the greatest number of protons in its nucleus? gold mercury lead silver
lead
which of the following normally warms up slower when heat is applied?
water
during a very cold winter, water pipes sometimes burst because
water expands when freezjng
the lowest possible temperature in nature is
-273 C
a certain radioactive element has a half-life of 1 hour. if you start with a 1 gram sample of the element at noon, how much of this same element will be left at 3:00 pm?
0.125 grams
compared to the mass of a hydrogen atom the mass of an oxygen atom is
16 times greater
the nucleus of an electrically neutral ion atom contains 26 protons. how many electrons does this iron atom have?
26
if hypothetically 80% of the atoms of an element had an atomic mass of 80, and the other 20% with an atomic mass of 82, what is the approximate atomic mass of the element?
80.4 amu
the systematic names for water, ammonia, and methane are digydrogen monoxide, H2O; trihydrogen nitride, NH3; and tetrahydrogen carbide, CH4. Why do most people, including chemists, prefer to use the common names for these compounds?
ALL OF THE ABOVE shorter and easier, encountered frequently, widely known
when three-quarters of a container of hot water is poured into a second empty container, the second container then has
ALL OF THESE 3/4 the thermal energy, 3/4 volume of water, same temperature
aluminum ions carry a 3+ charge, and chloride ions carry a 1- charge. what would be the chemical formula for the ionic compound aluminum chloride?
AlCl3
water freezes at a temperature of
BOTH OF THESE 0C 273K
when an alpha particle is ejected from a nucleus, the nucleus then has less
BOTH mass and charge
the density of water at 4C will slightly increase when it is
NEITHER cooled or warmed
when a gamma ray is emitted by a nucleus, the nucleus then has appreciably less
NEITHER mass or charge
when nitrogen and fluorine combine to form a molecule, the most likely chemical formula is
NF3
the phase in which atoms and molecules no longer move is the
NONE OF THE ABOVE solid liquid gas
if an atom were the size of a baseball, its nucleus would be about the size of
a flea
to say that water has a high specific heat capacity is to say that water
absorbs a lot of energy for a small increase in temperature
what is a hydrogen bond?
an unusually strong dipole-dipole attraction
pour a liter of 40C water into a liter of 20C water and the final temperature of the two liters becomes
at or about 30C
which elements are some of the oldest known? what is your evidence? the oldest known elements are the ones with
atomic symbols that do NOT match their modern names
most alpha particles fired at a gold foil pass through i deflected because the
atoms of gold, like any others, are mostly empty space
you could swallow a capsule of geranium, Ge, without significant ill effects. if a proton were added to each germanium nucleus however, you would not want to swallow the capsule because the germanium wohld
become arsenic
heat energy is measured in units of
both joules and calories
name of the following compound: CaCl2
calcium chloride
if two protons are removed from an oxygen nucleus, the result is
carbon
on which temperature scale is 0 degrees the freezing point of water?
celcius
when a nucleus emits a beta particle, its atomic number
changes, but it's mass number remains constant
what is it that electrons have that protons always have in equal magnitude?
charge
when a beta particle is ejected from the nucleus, the nucleus then has a greater
charge
is the rearrangement of the pairing of atoms a physical of chemical change?
chemical because the atoms has changed partners
an atom loses and electron to another atom. is this an example of a physical or chemical change?
chemical change involving the formation of ions
someone argues that he or she doesn't drink tap water because it contains thousands of impure atoms in each glass. how would you respond in defense of the waters purity, if it indeed does contain thousands of atoms of some impurity per glass?
compared to the billions and billions of water molecules, a thousand atoms of something else is practically nothing
transfer of heat among air and water molecules causing weather patterns happens by
convection
when a bimetallic bar composed of copper and iron strips is heated, the bar bends towards the iron strip because
copper expands more than iron
to predict the approximate energy release of either a fission or a fusion reaction, explain how a physicist uses a table of nuclear masses and the equation E=mc2
find the change in mass and multiply by the speed of light squared
thermal convection is linked mostly to
fluids
when you touch a piece of ice with your finger, energy flows
from your finger to the ice
which of the following types of radiation penetrate most deeply into the body?
gamma rays
which radiation has no change in electrical charge of the nucleus associated with it?
gamma rays
which process would release energy from gold, fission or fusion? from carbon?
gold fission carbon fusion
if the same quantity of heat is added to both a full 1 liter and a full 2 liter container of water, the temperature change of water in the 1 liter container will be
half
a hydrogen atom does not form more than one covalent bond because it
has only one electron to share
the moderate temperatures of islands throughout the world has mainly to do with water's
high specific heat capacity
strontium, Sr, is especially dangerous to humans because it tends to accumulate in calcium-rich bone marrow tissues. this fact relates to the organization of the periodic table in that strontium and calcium are both
in the same vertical columns
generally speaking, the larger the nucleus is, the greater its
instability
which would you expect to have a higher melting point: sodium chloride NaCl or aluminum oxide Al2O3?
the aluminum oxide has a higher melting point because of the greater charges of the ions, and hence the greater force of attractions between them
why are the atomic masses listed in the periodic table not whole numbers?
the atomic masses are average atomic masses
coal contains only minute quantities of radioactive materials, yet there is more environmental radiation surrounding a coal-fired power plant than a fission power plant. this indicated that
the coal fired power plant contains none of the radiation it releases
the white hot sparks from a sparkler that strike your skin don't cause injury becYse
the energy per molecule is high, but the total energy transferred is small
what chemical change occurs when a wax candle burns?
the heated wax molecules combine with oxygen molecules
why are ion-dipole attractions stronger then dipole-dipole attractions?
the magnitude of the electric charge associated with an ion is much greater
A substance consisting of which molecule shown below should have a higher boiling point? S=C=O O=C=O
the molecule on the left SCO because it has less symmetry
what makes an element distinct
the number of protons
imagine that you can see individual molecules. you watch a small collection of molecules that are moving around slowly while vibrating and bumping against each other. the slower-moving molecules then start to line up, but as they do so their vibrations increase. soon all the molecules are aligned and vibrating about fixed positions. what is happening?
the sample is being cooled and the material is freezing
in terms of the periodic table, is there an abrupt or gradual change between ionic and covalent bonds?
there is a gradual change: the farther apart, the more ionic
a measure of total energy of particles in a substance is
thermal energy
heat is simply another word for
thermal energy that flows from hot to cold
which are older, the atoms in the body of an elderly person or those in the body of a baby?
they are of the same age, which is appreciably older than the solar system
atoms of metallic elements can form ionic bonds, but they are not very good at forming covalent bonds, why?
they have a great tendency to loose electrons
how many different elements are in a water molecule
two
which of these atoms has the greatest number of electrons when neutral? helium carbon iron gold uranium
uranium
which of these atoms has the most mass? hydrogen iron lead uranium
uranium