Chapter 17: Physical Science
of the four boxes shown above, which represent a pure elemental material?
A and C
In the boxes shown above, each solid circle represents an atom of the same element. How many different types of molecules are depicted in the above transformation?
B
of the four boxes shown above, which represents a pure compound?
B
basic research
a branch of scientific research that focuses on a greater understanding of how the natural world operates
applied research
a branch of scientific research that focuses on developing applications built upon the principles discovered through basic research
physical change
a change in which a substance changes one or more of its physical properties without transforming it into a new substance
chemical change
a change in which the atoms of one or more substances are rearranged into one or more new substances
compound
a material in which atoms of different elements are bonded to one another
elemental formula
a notation that uses the atomic symbol and sometimes a numerical subscript to denote how atoms of the element are bonded together
chemical formula
a notation used to indicate the composition of a compound, consisting of the atomic symbols for the different elements of the compound and numerical subscripts indicating the ratio in which the atoms combine
chemical property
a property that characterizes the ability of a substance to undergo a change that transforms it into a different substance
when the atoms of a material vibrate in a fixed three-dimensional state, the material is
a solid
molecule
a submicroscopic particle consisting of a group of atoms
condensation
a transformation from a gas to a liquid
freezing
a transformation from a liquid to a solid
melting
a transformation from a solid to a liquid
evaporation
a transformation to a liquid to a gas
physical property
any physical attribute of a substance, such as color, density, or hardness
most chemists focus on
applied research to provide us with new technology
the halogens
are all of the above
during a chemical change
atoms change partners to form a new material
the evaporation of a liquid is also called
boiling
is the following transformation representative of a physical change or chemical change?
chemical because the atoms are connected differently
which of the following causes a chemical change in a substance?
eating a slice of cheese
boiling
evaporation in which bubbles form beneath the liquid surface
molecules are of the microscopic realm
false
sodium chloride is toxic because of all the sodium metal it contains
false
the freezing of water is an example is a chemical change
false
Which phase of matter responds dramatically to changes in pressure?
gases
a compound is made of different kinds of atoms bonded together
in definite proportions
which of the following is classifies as nonmetal?
iodine
the circles in the boxes shown above represent the submicroscopic particles of a material in its three phases. From left to right these are
liquid, solid, and gas
solid
matter that has a definite volume and a definite shape
liquid
matter that has a definite volume but no definite shape, assuming the shape of its container
gas
matter that has neither a definite volume nor a definite shape, always filling any space available to it
are atoms made of molecules or are molecules made of atoms?
molecules are made of atoms
submicroscopic
refers to the realm of atoms and molecules, which is a realm so small that we are unable to observe it directly with optical microscopes
moving from left to right across any period of the periodic table, the atoms become
smaller in size
The number of different elements known to humankind are
somewhat more than 100
Molecules exist at what level?
submicroscopic
chemical reaction
synonymous with chemical change
heat of fusion
the amount of energy needed to change any substance from solid to liquid, which is the same amount of energy released when the substance transformation from a liquid to a solid
heat of vaporization
the amount of energy required to change any substance from liquid to gas, which is the same amount of energy released when the substance transforms from a gas to a liquid
chemical bond
the force of attraction between two atoms that holds them together
which of the following statements is true about compounds?
they are composed of different elements bonded together
a compound is made of atoms from different elements
true
another name for water is dihydrogen monoxide
true
