REVIEW SCIENCE MIDTERM
the charge on a proton is
+1e
all atoms of the same element have the same number of electrons and protons, but may have different numbers of neutrons.
...
the number of degrees between the freezing point of water and the boiling point of water on the Celsius scale is
100
the number of electrons that may be held in the third energy level of an atom is
18
a common isotope of Carbon has an atomic number of 6 and a mass number of 13. how many neutrons are in an atom of this isotope?
7
a common isotope of iron (Fe) has an atomic number of 26 and a mass number of 56. the total number of subatomic particles in the nucleus is
82
The lowest possible temperature, approximately -273ºC, is referred to as ____________________.
Absolute zero
The temperature of an object increases when it ____________________ radiation.
Absorbs
As you add thermal energy to an object, its temperature will increase. Name two factors that will affect how much the temperature of a substance will change.
Answers may vary. Correct answers include: 1. Mass 2. Specific heat 3. Quantity of thermal energy added * The original temperature of a substance will also affect the temperature change but to a negligible amount, especially at ordinary temperatures.
List two examples of natural convection.
Answers may vary. Correct answers include: 1. Sea breeze 2. Cooking on a gas stove 3. Smoke rising in a chimney 4. Air circulating in a room heated by a radiator
The transfer of heat by direct contact between particles of matter is called?
Conduction
A sea breeze represents a transfer of heat by natural what?
Convection
It takes 504 joules to raise the temperature of 2.00 kilograms of a substance from 10.8ºC to 15ºC. What is the specific heat of the unknown substance?
E = m Cp(T2 - T1) 504 J = 2.00 kg (Cp )(15.0ºC - 10.8ºC) Cp = ; Cp = 60.0
What is the process that causes liquid water to change to a gas at room temperature?
Evaporation
The temperature scale on which water freezes at 32 degrees and boils at 212 degrees is the ____________________ scale.
Fahrenheit
32°F or 0°C, the temperature at which liquid water turns to solid ice, is called the ____________________ of water?
Freezing point
A mixture containing more than one type of matter, samples of which are not made of the same proportions of matter, is a(n) ____________________ mixture.
Heterogeneous
Name two properties that make a substance a good thermal conductor.
High density
What mixture that contains more than one type of matter and is the same throughout?
Homogeneous
The melting point of aluminum is greater than the melting point of lead because of the greater _________________________ of aluminum.
Intermolecular forces
What is the metric unit for measuring?
Joule
The temperature at which a substance changes from a solid to a liquid is?
Melting point
Matter, including elements and compounds, that cannot be separated into other types of matter by physical means is known as a(n) ____________________.
Pure substance
The phase of matter to hold its shape without flowing is the ____________________ phase.
Solid
List the four phases of matter in order from lowest thermal energy to highest thermal energy.
Solid, liquid, gas, plasma
In which phase of matter are intermolecular forces strongest?
Solids
The property of a material that indicates the amount of heat needed to raise the temperature of one kilogram by one degree Celsius is ___________________.
Specific heat
What is the name for the process during which a substance changes directly from a solid phase to the gas phase without becoming a liquid?
Sublimation
A cold winter night in Minnesota is measured at -58° Fahrenheit. What temperature would Canadian relatives measure that to be on the Celsius scale?
TCelsius = (TFahrenheit - 32); TCelsius = (-58 - 32); TCelsius = (-90); TCelsius = -50°C OR TCelsius = (TFahrenheit + 40) - 40; TCelsius = (-18) - 40; TCelsius = (-10) - 40; = -50°C
The average human body temperature is 98.6° on the Fahrenheit scale. Calculate its equivalent on the Celsius scale.
TCelsius = (TFahrenheit - 32); TCelsius = (98.6 - 32); TCelsius = (66.6); TCelsius = 37°C OR TCelsius = (TFahrenheit + 40) - 40; TCelsius = (138.6) - 40; TCelsius = 77 - 40; = 37°C
Calculate the Kelvin scale equivalent of 123º Celsius.
TKelvin = TCelsius + 273 TKelvin = 123°C + 273 TKelvin = 396k PTS: 1 DIF: intermediate REF: section 11.1
What does temperature measure?
Temperature is the measure of the kinetic energy per molecule due to random motion.
Joules, calories, and Btu's are all units used to measure ______________________________. .
Thermal energy
An instrument used to measure temperature is called a(n) ____________________.
Thermometer
condensation occurs when
a gas changes to a liquid
evaporation occurs when
a liquid changes to a gas
Two containers of water are placed side-by-side. Container A holds 400 kg of water at 20ºC. Container B holds 40 kg of water at 100ºC. The two containers are connected by a copper rod that will conduct heat between the containers. a. Which container possesses more thermal energy? b. In which direction will heat flow?
a. Container A possesses more thermal energy. b. Heat will flow from container B to container A
the lowest possible temperature, approximately -273 degrees C, is referred to as
absolute zero
the smallest particle of an element that retains the identity of the element is an
atom
the "building blocks" of matter
atoms and molecules
the temperature at which water changes to steam is known as the
boiling point
the proton's ______ is equal and opposite to the electron's
charge
a substance made of two or more elements that cannot be separated by physical means is called a
compound
the property that gives objects the ability to bounce is
elasticity
electrons are bound to the nucleus by
electromagnetic force
an atom contains ____ in various energy levels
electrons
When two substances in thermal contact starting at different temperatures reach the same temperature, their condition of thermal "balance" is called thermal ____________________.
equilibrium
the transformation of a liquid to a gas that serves as a cooling process is called
evaporation
the temperature scale on which water freezes at 32 degrees and boils at 212 degrees is the __________ scale
fahrenheit
Heat is defined as the
flow of thermal energy from one object to another object.
32 degrees F or 0 degrees C, the temperature at which liquid water turns into solid ice, is called the __________ of water
freezing point
Thermal energy that is moving or capable of moving is called ____________________.
heat
How many calories of energy does it take to increase the temperature of 400 grams of water by 10 degrees Celsius?
heat added = mass of material specific heat of material total change in temperature heat = 400 grams 1 calorie/gram degree Celsius 10 degrees Celsius heat = 4000 calories
a mixture containing more than one type of matter, samples of which are not made of the same proportions of matter, is a __________ mixture
heterogeneous
Heat flows from a body of ____________________ temperature to a body of ____________________ temperature
higher, lower
the name for a mixture in which all samples are made up of the same proportions of matter is
homogenous
a compound
is made of more than one kind of element, cannot be separated by physical means, and is classified as a substance
atoms having the same atomic number but different mass number are described as
isotopes
atoms with the same atomic number but different atomic mass are
isotopes
The heat unit, Calorie, written with a capital C is also known as a ___________________.
kilocalorie
the property of gold which would make it most useful in the creation of jewelry is
malleability
the number of protons plus the number of neutrons in the nucleus of an atom is known as the
mass number
the density of a solid material depends on two things; how closely atoms or molecules are packed and
mass of individual atoms or molecules
the mass of an atom is determined mainly by the
mass of the neutrons and protons
the term used to describe anything that has mass and takes up space is
matter
A swimming pool containing water at a temperature of 25 degrees Celsius contains more or less thermal energy that a coffee cup of boiling water?
more
compared to protons, electrons have
much smaller mass and opposite charge
a particle with zero charge found in the nucleus of an atoms is called a
neutron
the most abundant gas in earth's atmosphere is
nitrogen
protons and neutrons are found grouped together in the
nucleus
the tiny core of an atom containing most of the mass of the atom is the
nucleus
what do we call the tiny core at the center of an atom, containing most of the atom's mass and all of its positive charge?
nucleus
the phase of matter represented in a flash of lightning is
plasma
which phase of matter is most common in the universe
plasma
a charged particle that accounts for nearly half the mass of an atoms is the
proton
the ______ is one kind of particle that makes up the atom and carries a positive charge
proton
all Lithium atoms contain the same number of
protons
Matter, including elements and compounds, that cannot be separated into other types of matter by physical means is known as a
pure substance
the nucleus of an atom that spontaneously breaks up to emits particles or pure energy may be called
radioactive
two negative charges will _____ one another
repel
viscosity is a measure of a material's
resistance to flow
in general, the most dense phase of matter on Earth is
solid
the phase of matter most likely to be present at absolute zero would be
solid
the phase of matter to hold its shape without flowing is the ______ phase
solid
list the phases of water in order, from the phase with the slowest molecular movement to the phase with the fastest molecular movement
solid--> liquid--> gas
each element emits a characteristic pattern of __________ when viewed through a spectroscope
spectral lines
the instrument used to separate the light given off by electrons into different colors is called a
spectroscope
protons and neutrons in the nucleus are held together by
strong nuclear force
the process during which a substance changes from a solid directly to a gas without becoming a liquid is known as
sublimation
why don't all the electrons in an atom fall to the lowest energy level?
the lowest energy level can only hod 2 electrons
atomic number is
the number of protons in an atom
the number of protons is _____ between the two isotopes
the same
atoms of the same element may contain
the same number of protons but a different number of neutrons
the strongest force in the universe is
the strong nuclear force
What is the name generally given to a material that conducts heat poorly?
thermal insulator
By which method is heat transferred from the Sun to Earth?
thermal radiation
an instrument used to measure temperature is called a
thermometer
they physics property that makes ketchup difficult to pour is its
viscosity
solids retain their shape and size, if kept at constant temperature and pressure. at a constant temperature and pressure, liquids retain their
volume
the charge on a complete atom is equal to
zero
