Chemistry Final
in 1911, rutherford conducted his now famous gold foil experiment. During the experiment, alpha particles bombarded a thin piece of gold foil. The alpha particles were expected to pass easily through the gold foil. every now and then, however, an alpha particle bounced back - an unexpected result. Rutherford concluded that these particles were striking
a tiny region of positive charge
write the group number for the following elements a. alkali metals b. halogens c. transition metals
a. 1 b. 7 c. 3-12
state the valence electrons each statement has a. O b. Br c. He d.K
a. 6 b. 7 c. 2 d. 1
indicate if each orbital notation is valid or invalid. If invalid circle the error and state which rule is broken a. 1s ↑↓ 2s ↑↓ 2p ↑↓ ↑↓ ↑↓ 3s ↑↓ 3p ↑↑ ↑ ↑ b. 1s ↑↓ 2s ↑↓ 2p ↑↓↑↓↑↓ 3s ↑↓ 3p ↑ ↑ _ 4s ↑
a. invalid (↑↑) pali exclusion b. invalid (empty space) abufu principle
label each characteristic as metal, nonmetal, and metalloid a. ductile b. gas c. staircase d. left of staircase
a. metals b. nonmetals c. metalloid d. metals
draw one orbital that is represented by designations. Must be a shape and they should be proportional a. 2s b. 3p c. 3s
a. sphere b. propeller c. bigger sphere
Which of the following is not one of the 5 principles of Dalton's theory?
all atoms have similar physical and chemical properties
what is the fomula unit of aluminum oxide?
al₂0₃
compared with the elements at the left end of the p-black element group, the elements at the right end
are less metallic
the atomic symbol for Beryllium, ⁹₄Be, indicates that the
atomic number is 4
Which feature of Dalton's atomic theory is different from modern atomic theory?
atoms cannot be subdivided
what causes dipole interactions
attraction between polar molecules
what causes hydrogen bonding
bonding of a covalently bonded hydrogen atom with an unshaped electron pair
how is a pair of molecular orbitals formed
by the overlap of two atomic orbitals from different atom
The law of multiple proportions is demonstrated by the compounds
co and co₂
when one atom contributes both bonding electrons in a single covalent bond, the bond is called an
coordinate covalent bond
a 3 dimensional arrangement of particle in an ionic solid is called
crystal lattice
the VSEPR model is used mainly to
determine molecular shape
a measure of the ability of an atom in a chemical compound to attract electrons from another atom in the compound is called
electronegativity
a nonpolar covalent bond is one in which
electrons are shared equally
According to the law of conservation of mass, when sodium, hydrogen and oxygen react to form a compound, the mass of the compound will be
equal to the sum of the masses of the reactants
shorthand electron configuration for copper
exception
a light is emitted from a gaseous atom when an electron moves to its ground state from an
excited state
how many electrons are shared in a double covalent bond
four
as the atomic number increases within a group of elements, the atomic radius
generally increases
the lowest energy state of an atom is its
ground state
all the alkali metal elements are found on the periodic table in
group 1
which periodic group or family of elements is not correctly matched with its common family name?
group 3 - alkali metals
which of the following covalent bonds is the most polar?
h-f
compared with ionic compounds, molecular compounds
having lower melting points
the mixing of two or more atomic orbitals of similar energies on the same atom to produce new orbitals of equal energies is called
hybridization
which of the following elements is a transition metal?
iron
the overall charge of a formula unit for an ionic compound
is always 0
which of the following elements is most similar behavior to calcium?
magnesium
which of the following pairs of electrons is most likely to form an ionic compound
magnesium and flourine
Isotopes are atoms of the same element but have different
masses
molecules containing only polar covalent bonds __________
may or may not be polar
what is thought to cause the dispersion forces
motion of electrons
electrons can be found
moving rapidly outside the nucleus
to take a weighted average of all the naturally occuring isotopes of an element in order to arrive at an average atomic mass, you would
multiply the mass of each isotope by the decimal fraction representing its abundance naturally, then add all these products together
the behavior of cathode rays in a glass tube containing gas at low pressure led to conclude that the rays are composed of
negative particles
Experiments with cathode rays being deflected by a magnetic field show that cathode rays are composed of particles that are
negatively charged
The metalloids are located on the periodic table between
nonmetals and metal
most of the volume of an atom is occupied by the
nucleus
The diagram ↑↓ represents two electrons with
opposite spin states
Which of the following theories provides information concerning both molecular shape and molecuar bonding
orbital hybridization
Acording to vsepr theory, molecules adjust thier shapes to keep which of the following as far apart as possible
pairs of valence electrons
most chemical bonds are
partly ionic and partly covalent
a horizontal row in the periodic table is called a(n)
period
the side by side overlap of p orbitals produces what kind of bond
pi bond
Mendeleev organized the chemical elements based on their
properties
shorthand electron configuration for strontium
(Kr)5s²
In an experiment, Alex and Rachel discover that their sample of table salt, also known as sodium chloride, NaCI, consists of 39.34% by mass sodium, Na, and 60.66% by mass chlorine, Cl. Later, alex wonders what that percentage of Na might be in the table salt in his saltshaker at home. Rachel tells him, correctly that it is
39.34%
how many electrons does carbon ave in its outermost shell?
4
carbon-14 has 8 neutrons. What is the atomic number of carbon - 14?
6
order the following in decreasing electronegativity : Ge, Br, Se
Br > Se > Ge
which is larger Cl or Cl⁻
Cl⁻
which of the following elements is not a metal H,K,Na,Fr
H
neutral atoms contain equal numbers of
protons and electrons
except for in the simplest type of hydrogen atom, all nuclei consist of
protons and neutrons
as the mass number of an element's isotopes of an element increases, the number of protons
remains the same
bonding in molecules or ions that cannot be correctly represented by a single lewis structure is
resonance
the formula unit of an ionic compound shows the
simplest ratio of the ions
Protons are bound together by
strong nuclear forces
the electron configuration below represents a ground state atom of which element 1s²2s²2p⁶3s²3p⁴
sulfur
what is the basis of a metallic bond?
the attraction of metal ions to mobile electrons
the ancient Greek philosopher who first proposed the notion of the atom was
Democritus
the octet rule states that atoms tend to have
the electron configuration of a noble gas
describe shielding
the electrons of the inner energy levels block out the charge from the outer energy levels
the symbol o+ is placed next to which of the following
the less electronegative atom in a polar covalent bond
the atomic number of an element is
the number of protons in each atom of the element
the periodic law states that
the physical and chemical properties of the elements are functions of their atomic number
According to the law of definite proportions, any two samples of KCl will have
the same elements in the same proportions by mass
mass number is
the total number of protons and neutrons in an atom of the element
The average atomic mass of an element is
the weighted average of all naturally occurring isotopes of the element
what characteristic of metals makes them goof electrical conductors
they have mobile valance electrons
the total volume of the nucleus of an atom is
very small compared to the rest of the atom
the distance between corresponding points on adjacent waves is the wave's
wavelength
The discovery of the nucleus was a result of Rutherford's observation that a small percentage of the positively charged particles bombarding the metal's surface
were deflected back toward the source
the nuclear symbol for uranium-235 should be written as
²³⁵₉₂U
order K, Na, Cs in increasing atomic radius
Na < K < Cs
order the following in increasing ionization energy: F,C,Sn
Sn < C < F
which of the following is a pseudo noble gas electron configuration
1s²2s²2p⁶3s²3p⁶3d¹⁰
the number of valence electrons for group 2 elements is
2
what is the charge on the strontium ion?
2+
A molecule of carbon monoxide, co containing 1 g of carbon, 1.33 g of oxygen will combine with the carbon to form the molecule. What is the mass of oxygen in a sample of CO₂₂ containing 1 g of carbon?
2.66 g
the atomic number of nickle-60 is 28 how many neutrons does this isotope have
32 neutrons
what is the atomic number of the element with the noble - gas notation (Kr)5s1
37
cobalt - 60 with a half life of 5 years, is used in cancer radiation treatments. If a 30.0 g sample, how much would be left after 15 years?
37.5 g
an atom of potassium has 19 protons and 20 neutrons. Its mass number is
39
electrons mass number? charge? location?
0 - in orbit outside of nucleus
how many possible orientations does an s orbital have
1
protons mass number? charge? location?
1 + nucleus
neutrons mass number? charge? location?
1 0 nucleus
determine the wavelength for a wave with a frequency of 2.58 ∙ 10⁴ Hz
1.16 ∙ 10⁻⁶
a neutral atom of silicon - 30 contains 14 protons. How many electrons does it have?
14
oxygen has 3 naturally occuring isotopes in the following proportions: Oxygen-16, 99.72% (15.99491 amu); oxygen 17, 0.038000 ( 16.9913 amu); oxygen 18, 0.20000% (17.9916 amu); what is the average atomic mass of oxygen
15.999 amu
the halogens are located on the periodic table in group
17
K⁺ had 19 protons. How many electrons does it have? is this cation or anion?
19 electrons, cation
The atomic mass of an atom ia 12 amu, and the atomic mass of an atom is 16 amu. To produce Co₂, 16 g of oxygen combine with 12 g of carbon. To produce Co₂, 32 g of oxygen combine with 12 g of carbon. The ratio of the mass of oxygen in Co₂ to the mass of Co is
1:2
orbital notation for aluminum
1s ↑↓ 2s ↑↓ 2p ↑↓ ↑↓ ↑↓ 3s ↑↓ 3p ↑
what is the correct noble-gas notation for the electron configuration of an atom of chlorine
[Ne] 3s² 3p⁵
Rtherford's gold foil experiment led him to conclude that
a dense region of positive charge existed somewhere in an atom
an ionic bond is
a force that holds together atoms that are oppositely charged
ionic bonds generally occur between
a metal and a nonmetal
Rutherford called the region that deflected the alpha particles
a nucleus
