Physical Science Exam 4 Practice
The alkali metals (group 1) tend to form 1+ ions while the alkali earth metals (group 2) tend to form 2+ ions because
The charges of these ions corresponds to the number of valence electrons that may be lost
How does an electron get from one lobe of a p orbital to the other?
The electron actually exists in both lobes at the same time
It's impossible for a hydrogen atom to emit an alpha particle. True or False?
True
An element will decay to an element with higher atomic number in the periodic table if it emits
a beta particle
how might the spectrum of an atom appear if its electrons were not restricted to particular energy levels?
a broad spectrum of all colors would be observed
The milky way is
a spiral galaxy
the milky way is
a spiral galaxy
Which experiences the greatest electrical force in an electric field, electron, gamma ray, beta particle, a alpha particle, or all experience the same force?
alpha particle
an atom with an imbalance of electrons to protons is
an ion
In which city is Polaris highest in the sky: -singapore -denver -mexico city -anchorage -all the same, depending on the time of night
anchorage
If a alpha and beta particle have the same energy, which particle will penetrate farthest in an object
beta particle
the masses of stars are found by measurements of
binaries
The H-R Diagram, an important tool of astronomers, relates stellar temperature to stellar
brightness
when a nucleus admits a beta particle, its atomic number
changes, but its mass number remains constant
The temperature of a star is evidenced by its
color
Energy released by the sun results from the process wherein automatic nuclei
combine
Thermonuclear fusion occurs mainly in the
cores of stars
most of the stars in colliding galaxies a) do not make contact with one another b) undergo accelerated collapse c)coalesce into larger stars d) end up as binaries
do not make contact with one another
The volume of matter comes mostly from its
electrons
Compared to most stellar objects, quasars are more
energetic, distant and puzzling
The number of elements in a period is
equal to the electron capacity of the shells
Which experiences the least electrical force (zero force) in an electric field?
gamma ray
which radiation has no electrical charge associated with it?
gamma rays
The reason plutonium is not found in any appreciable amounts in natural ore deposits is because it
has a short half-life
If one neutron is added to a helium nucleus the result is
helium
The longest living stars are those of
high mass
The most abundant element in the universe is
hydrogen
Electrical forces inside a nucleus contribute nuclear
instability
Generally speaking, the larger a nucleus is, the greater its
instability
generally speaking, the larger the nucleus is, the greater its
instability
In both fission and fusion, mass
is changed to the form of kinetic energy
in both fission and fusion, mass
is changed to the form of kinetic energy
AN electron in a 7s orbital has more energy than one in a 1s orbital because
its principle quantum number is higher
Compared to the sum of the masses of all the individual nucleons in their separate states that make up a nucleus, the mass of the composite nucleus is
less
When an alpha particle is ejected from a nucleus, the nucleus then has less
mass and charge
Compared to a neutron bouncing off a carbon nucleus, a neutron bouncing off a hydrogen nucleus loses
more speed
When a gamma ray is emitted by a nucleus, the nucleus then has appreciably less
neither mass nor charge
Which is electrically neutral? neutron, electron, proton
neutron
Dif isotopes of an element have different numbers of
neutrons
If the sun collapsed to become a black hole, the earth's gravitational attraction to it would be
no different
Compared to protons, the reason neutrons are effective nuclear bullets in nuclear reactions is because a neutron has, more penetrating power than a proton, or more mass than a proton, or a wider cross section than a proton?
none of these
When thorium (A = 90) emits a beta particle, the resulting nucleus has atomic number 88, 89, 90, or 92?
none of these
The mass of a nucleus is exactly equal to the sum of the masses of it's individual
nucleons, neutrons or protons? none of these
The nucleon has more mass when it is
outside the nucleus
The distances of stars is found by
parallax
the atomic number of an element is the same as the number of its
protons
the weight of matter comes mostly from its
protons and neutrons
electrical forces within an atomic nucleus tend to
push it apart
After our sun burns it's supply of hydrogen, it will become a
red giant
when a star collapses to become a black hole its mass
remains unchanged
artificially induced radioactive elements generally have
short half lives
A pulsar is likely a
spinning neutron star
The half-life of a radioactive substance is independent of
the age of the substance, the number (if large enough) of atoms in the substance, the temperature of the substance and whether the substance exists in an elementary state or in a compound
Summer and winter constellations are different because
the night sky faces in different directions in summer and winter
Polaris is always directly overhead
the north pole
what makes an element distinct
the number of protons
A black hole is
the remains of a giant collapsed star
Suppose a hydrogen bomb were exploded in a box that could contain all the energy released by the explosion. Compared to the weight of the box before the explosions, the weight of the box after the explosion would be
the same
it is relatively easy to pull an electron away from a potassium atom, but very difficult to remove a second one because
the second electron experiences a far greater nuclear charge
the star nearest the earth is
the sun
How many different elements are in a water molecule
two-hydrogen and oxygen
A sample of relatively active radioactive material is somewhat
warmer than the enviroment
A certain radioactive isotope placed near a Geiger counter registers 120 counts per minute. If the half life of the isotope is one day, what will the count rate be at the end of four days?
7.5 counts/min
Compared to the mass of a H atom, the mass of a an O atom is
8 times greater
When U-239 emits a beta particle, the nucleus left behind has
93 protons
Why are the atomic masses listed in the periodic table not whole numbers?
Atomic masses are an average of an elements isotopes
Evidence for the existence of neutrons did not come until many years after the discoveries of elecctrons and protons. why?
Because the nuetron lacks an electrical charge
Which color of light comes from the higher energy transition, red or blue?
Blue is higher freq, corresponds to higher energy level transition
Which force determines the chemical properties of an atom?
Electrical force
Uranium-235, U-238, U-239 are different
Isotopes- same # protons but dif # nuetrons
How can a hydrogen atom, which has only one electron, have so many spectral lines?
One electron can be boosted to many dif energy levels