Phys sci test 3 quizes XD Flashcards
As the temperature of an object decreases, the average speed of its molecules
decreases
Absolute zero describes
0 K
Your body judges temperature
very poorly, sensing onlly heat flow
Which temperature scale measures the absolute temperature of an object?
kelvin
Which of the following is NOT a principle of Caloric Theory?
Caloric causes atoms to vibrate
As a liquid at its boiling point goes through a phase change to a vapor, heat is absorbed and the temperature
stays the same
Doubling the temperature corresponds to doubling the internal energy in the ____________ temperature scale.
Kelvin
Anywhere there is a temperature difference, you can expect
energy flow from the hot object to the cold object.
In which of the following are the positions of the molecules fixed?
solids
Which of the following is most easily compressed?
gases
The transfer of energy by collisions between molecules is called
conduction
Convection may occur in
liquids and gases
Which objects emit radiant energy?
all objects
The temperature of an object that is a net absorber of radiation will
increase
Which law says that energy becomes less useable (some is wasted)?
second law of thermodynamics
Which law says that energy is conserved?
first law of thermodynamics
The amount of heat needed to increase the temperature of 1 gram of a substance by 1 degree Celsius is known as
specific heat.
what are the three mechanisms for heat flow?
radiation, convection, conduction
Liquid water MUST be at its boiling point before any of its molecules can go into the gas phase.
FALSE
The originator of the idea that matter is made up of atoms is
Democritus
The atomic number of an element is the number of _____________ in the nucleus.
protons
Isotopes of an element have DIFFERENT numbers of
neutrons
When a pure gaseous element is heated it will produce a _______ spectrum of light
line spectrum
The classical model of atoms was not able to explain
the stability of atoms
Louis de Broglie originated the idea that electrons might behave as
both particles and waves
According to the Bohr model of the atom, light is emitted or absorbed
when electrons change orbits
The Bohr model of the atom works
only for hydrogen
The quantum mechanics model predicts
the positions of electrons using probability distributions
J. J. Thompson discovered the subatomic particle called the
electron
The inner shell of an atom can contain no more than
2 electrons
The outermost shell of an atom containing any electrons can hold no more than ________ electrons.
8 electrons
The vertical columns in the periodic table are called
groups
The chemical properties of an atom are determined by
the outer shell electrons
Each vertical column of the periodic table includes elements with chemical characteristics that are, in general,
similar
An oxygen atom, O, is in group VI and would like to gain ____ electrons in a chemical reaction.
2
In a positive ion the number of protons is ____________ the number of electrons.
greater than
In a chemical reaction the element sodium, Na, in group I will gain or lose an electron
lose an electron
Ionic bonds are formed when
electrons are transferred between atoms
A negative ion is formed when an atom
gains an electron
Ionic bonds form between
a metal atom and a nonmetal atom
Covalent bonds are formed when
atoms share pairs of electrons.
Atoms react so that they end up with _____ electrons in their outer shell.
8
An alkali metal atom
has one electron in its outer shell
The outer electrons of atoms that are involved in chemical bonding are referred to as ________ electrons.
valence
An atom is the
smallest unit of an element that can exist alone.
first law of thermodynamics
energy(heat)-work=change in internal energy
Second law of thermodynamics
heat flows from object of higher temperature to lower temperature
