Unit 4: CHEMISTRY REVIEW
What is the net ionic charge of beryllium? +1, -1, -2, +2
+2
Express as ordinary numbers. 8.97 x 10-3 =
0.00897
What is the electron structure of a nitrogen atom?
1s 12s 12p 3
Express in scientific notation. 0.000543 =
5.43 x 10 -4
Round 6.362 to 2 significant digits:
6.4
Give the number of valence electrons for fluorine.
7
ionic bond
A bond between atoms of greatly differing electronegativities, usually a metal and a nonmetal; a transfer of one or more valence electrons from one atom (low electronegativity) toward another (high electronegativity); bonds exist between unlike electrical charges (+ and - ions).
covalent bond
A chemical bond between atoms with similar electronegativities, usually nonmetals; valence electrons are shared.
inorganic
A compound that does not contain the element carbon.
theory
A generalized model used to explain observations, to answer questions, and to predict answers to related evidence and problems.
period
A horizontal row in the periodic table.
Avogadro's hypothesis
A hypothesis that equal volumes of gas under equal conditions have equal numbers of molecules.
electronegativity
A measure of the ability of atoms to attract electrons within a chemical bond.
mass
A measure of the quantity of matter in an object.
The bonding of two atoms will most likely occur if
A more stable state can result from the union.
electron
A negative particle basic to matter; located outside the nucleus.
deductive reasoning
A prediction made or conclusion drawn from insight gained from an established principle.
element
A primary substance that cannot be divided into separate substances; one of about 112 different basic varieties of matter making up the universe.
law
A relationship that is accepted as true and no longer needs to be tested and verified.
suspension
A temporary heterogeneous mixture that separates into individual components with time.
colloid
A uniform dispersion, heterogeneous in nature, between two or more substances.
solution
A uniform mixture of molecules or ions of one substance in another.
group
A vertical columns of the periodic table; groups have similar valence electron structure and similar chemical and physical properties.
beta particle
An electron or particle similar to an electron emitted from the nucleus of a radioactive element.
hypothesis
An initial proposed explanation for the phenomenon.
nuclide
An isotope of a radioactive element.
polar
An unequal, unbalanced distribution of electrons in a molecule causing one portion to be partially positive (+) and another to be partially negative (-).
ion
Atom or group of atoms with a net charge caused by unequal numbers of electrons and protons.
Predict the following chemical formulas.- Calcium Chloride - & Aluminum Oxide -
CaCl2, Al2O3
heterogeneous
Composed of dissimilar parts which can be separated easily and which are unevenly distributed in the mixture.
If D+2 would react with E-1, what do you predict to be the formula?
DE2
What is meant by "the energy of an electron is quantized"?
Each electron around an atom has a discrete measure of energy.
Which statements are correct about a group?
Each member of the group has the same number of electrons in the outer shell., The elements in each group have similar chemical properties.
quantum
Energy available or given off in specific, predictable quantities
homogeneous
Even distribution of parts throughout the whole mixture; not easily separated into individual components.
alpha particle
Helium nucleus emitted from the nucleus of a decaying isotope.
gamma ray
High energy ray of energy emitted from some radioactive atoms.
precision
How spread out the results of an experiment are or, how repeatable measurements are; often dependent on the certainty with which an estimation can be made.
presupposition
Initial idea which is believed to be true and is used as a basis (starting point) from which further reasoning and conclusions are made.
isotope
Members of the same element (same atomic number) but different mass number due to different numbers of neutrons in the nucleus.
Which element would have the greatest attraction for the calcium electrons (if they could combine)?
N
neutron
Neutral particle found in the nucleus; mass about equal to that of a proton.
mole
One atomic weight of an atom or molecular weight of a molecule expressed in grams. One mole of any substance contains 6.02 x 10 23 atoms or molecules. One mole of any gas at STP will occupy 22.4 L.
proton
One of the particles of the nucleus; positively charged.
reactant
One of the starting substances (ingredients) that is involved in a chemical reaction.
objective
Real reasoning based on data or facts.
Give the symbol for the element that has an electron configuration of 1s22s22p63s23p4.
S (sulfur)
_____states that the physical and chemical properties of the elements are periodic within the sequence of their atomic numbers.
The Periodic Law
parent
The beginning nuclide in the radioactive decay chain.
metallic bond
The bond formed in metals, holding metals together; delocalized bond with very fluid, mobile electrons; electron mobility accounts for ease of electrical conductivity.
energy level
The broad bands or regions located around the nucleus where the electrons are found.
nucleus
The central core of the atom containing most of the mass and made up of protons and neutrons.
accuracy
The correctness of a measurement when compared to the actual value.
mass defect
The difference between the mass of a nucleus and the sum of masses of its components; equivalent to binding energy according to E=mc 2.
Charles' Law
The direct relationship between temperature and volume of gases such that as temperature (absolute scale) increases, volume increases by the same fraction of change. Pressure and volume remain constant.
spectrum
The distribution of light when passed through a prism or other device in order to break the light into its individual components.
ion charge
The electron charge an atomic particle carries.
ionization energy
The energy necessary to overcome the attractions of electrons to the nucleus of an atom so as to remove electrons from the atom.
kinetic energy
The energy of motion which is represented as K.E.=1/2 mv 2 where m = mass, and v = velocity of the particle in motion.
nonmetal
The group of elements that have high electronegativities and are poor conductors of electricity and heat; mostly liquids and gases.
metal
The group of elements that tend to give up electrons and are good conductors of electricity and heat; solids except for mercury.
Boyle's Law
The inverse relationship between pressure and volume of gases such that as pressure increases, volume decreases by the same fraction of change. Temperature and number of molecules remain constant.
Combined Gas Law
The mathematical relationship which contains the three variables of pressure, volume, and temperature. This law is derived from combining Boyle's and Charles' Laws into one.
polarity
The measure of the degree of charge separation within a polar molecule.
length
The measure of the distance from one point to another.
daughter
The nuclide produced from a radioactive decay.
Avogadro's number
The number of particles in a mole of a substance. Equals 6.02 x 10 23 particles per mole.
mass number
The number of protons plus neutrons in the nucleus.
diffusion
The process of intermingling molecules from one substance into another by random molecular motion.
Why does electronegativity decrease down a family?
The sizes of the atoms increase.
product
The substance yielded as a result of a chemical reaction.
equation
The symbolic representation of a chemical reaction based on the conservation of mass.
Kinetic Molecular Theory
The theory that all matter is particulate, in continuous motion, and increasingly spread out from solids to gases.
A hypothesis which appears to be verified by multiple experiments and/or researchers may become a
Theory
compound
Two or more elements chemically joined together such that the elements have lost their individual identity in favor of a new set of properties.
mixture
Two or more substances dispersed in one another but each retaining their own identity.
The scattering of light by a colloid is called the
Tyndall effect
radioactive
Unstable and capable of disintegrating into different elements, producing radiation and energy.
inverse relationship
When one variable becomes larger by a given factor and the other variable becomes smaller by the same factor.
direct relationship
When two variables change in the same direction, one remaining larger than the other by the same factor.
What causes the lines in the spectrum for elements?
a quantum release of energy as electrons drop back to their ground state
On the periodic table, elements are arranged by _____.
atomic number
What caused the bonding of two atoms which underwent an ionic bond?
attraction of opposite ions to each other
Density is _____ to pressure.
directly proportional
A quantum is a unit of
energy
atom
he simplest unit of an element that still retains the properties of that element.
Forming a hypothesis is accomplished through _______ reasoning
inductive
The rocks and minerals of the earth consist of _______ compounds.
inorganic
In a _____, the substances retain their individual chemical and physical properties
mixture
Which group, metals or nonmetals, has the greatest chance to gain electrons and to become negative ions?
nonmetals
Diatomic molecules will be ________ when they are composed of only one element.
nonpolar
The biosphere of the earth is made up of ______ compounds.
organic
An excellent tool to gauge the reliability of any theory is its capacity to generate accurate ________
predictions
What are the foundations of beliefs from which a person begins to reason called?
presupposition
A _____ is a uniform mixture of molecules or ions of one substance in another. These substance will not separate by ordinary means.
solution
volume
space occupied by a quantity of matter.
A direct relationship occurs when:
two variables decrease at the same time two variables increase at the same time
The outermost electrons in an atom are called ______ electrons.
valence
Which of the following is a chemical property?
volatility
When do electrons emit energy?
when moving to a lower orbit from an excited state