The fundamental charge discovered by Millikan has a specific value of:
1.6�10^?19 C
According to Thomson, electrons are attracted to ____________ charges and are repelled by ______ charges.
positive, negative
What law states that when two elements react to form more than one compound, a fixed mass of one element will react with masses of the other element in a ratio of small, whole numbers?
the law of multiple proportions
A 100 g sample comprised of molecule (A) is made up of 57.1 g of oxygen and 42.9 g of carbon. Another 100 g sample comprised of molecule (B) is made up of 72.7 g oxygen and 27.3 g carbon. What can be determined about molecule A and B?
Molecules A and B are different compounds, with B having twice the mass ratio of A
Who was the first person to propose the existence of the atom?
Democritus
According to Dalton's theory, atoms of a given element are:
identical in mass
extremely tiny
different from atoms of any other element
Who was the first person to show empirical evidence for the existence of atoms?
John Dalton
Whose view that matter as infinitely divisible was considered correct for most of the last two millenia?
Aristotle
According to Ernest Rutherford, what percent of an atom is empty space?
99.95
J.J. Thomson
discovered the electron by experimenting with an apparatus known as a cathode ray tube
Thomson proposed the following:
The particles in the cathode ray are attracted by positive (+) charges and repelled by negative (?) charges, so they must be negatively charged (by this time, it was known that like charges repel and opposite charges attract).
The particles are less massi
electrons
negatively charged, subatomic particles, each with a mass more than one thousand times less that of an atom
-1.602x10^-19 charge
Thomson proposed the ______________________ model
plum pudding" model
plum pudding" model
the negative electrons were represented by the raisins in the pudding and the dough contained the positive charge. Thomson's model of the atom did explain some of the electrical properties of the atom due to the electrons, but failed to recognize the posi
Hantaro Nagaoka
postulated a Saturn-like atom, consisting of a positively charged sphere surrounded by a halo of electrons
Robert A. Millikan
deduced the numerical values of the charge and mass of an electron
Robert Millikan used Thomson's existing data to
determine the mass of the electron.
Ernest Rutherford
postulated the structure of the atom's nucleus
who conducted a series of experiments in which they bombarded the atoms in a piece of gold foil with alpha particles?
Ernest Rutherford, Hans Geiger and Ernest Marsden
alpha particles
extremely small, positively charged clusters
Rutherford's conclusions
1. The volume occupied by an atom must consist of a large amount of empty space.
2. A small, relatively heavy, positively charged body, the nucleus, must reside at the center of each atom.
proton
the positively charged, subatomic particle found in the nucleus
1.602x10^-19 charge
James Chadwick
found evidence of neutrons
neutrons
uncharged, subatomic particles with a mass approximately the same as that of protons
0 charge
What subatomic particle determines the element that an atom belongs to?
proton
The prefix in subatomic tells us that subatomic particles are:
the basic building blocks of atoms
Which element weighs, on average, approximately one atomic mass unit?
hydrogen
What is the precise mass of the proton?
1.00727 amu
Which is typically greatest in magnitude for any atom?
mass number
Who determined the structure of the atomic nucleus?
Ernest Rutherford
The charges on the proton and electron are typically measured in:
coulombs
Which two subatomic particles would have a combined unit charge of 0?
electron, proton
Which has the smallest mass?
an electron
particles charge and location
proton: positive charge, within the nucleus
electron: negative charge, outside the nucleus
Which two particles have roughly the same mass?
proton and neutron
When considering precise mass, which particle has the greatest mass?
neutron
The mass number of an atom is equal to:
number of protons + number of neutrons
Knowing that one isotope is responsible for 69.15% of the mass, the remaining isotope must account for ____________________
the other 30.85%.
Atoms of the same element can have different:
mass numbers
average mass =
?i(fractional abundance �isotopic mass)i
1 amu=
1.6605�10?24 g.
An atomic nucleus:
has a mass that is less than the sum of the masses of its protons and neutrons
-mass defect
One atomic mass unit is equal to:
1.66�10?24 grams
One atomic mass unit is approximately equal to the mass of a proton.
The noble gases are also called the:
inert gases
Another word for period is:
series
The reason that atomic numbers are always integer values is because every element has:
a particular number of protons
The second element that was discovered that further corroborated Mendeleev's table was:
germanium
Which of the following scientists published tables with the elements arranged according to increasing atomic mass?
Dmitri Mendeleev, Lothar Meyer
The large block between groups 2 and 13 is called the __________________
transition metals.
Lithium and similar elements were found to react with oxygen in a ratio of _________, lithium to oxygen:
2:1
Dmitri Mendeleev began the organization of the periodic table using increasing atomic ___________. However, today's modern periodic table organizes elements by increasing atomic _____________
mass;number
_________________ highlights the periodicity, or recurring properties, of the elements.
Periodic law
The horizontal rows of the periodic table are known as:
The horizontal rows of the periodic table are known as:
All elements in group 2 are __________
metals.
prior to Bohr, the most updated version of atomic structure came courtesy of:
Ernest Rutherford
Beyond the orbital energy of the electron, which other values must also be quantized?
the angular momentum of the electron, the orbital radius of the electron, the energy of any photon absorbed or emitted by the electron
when an electron moves from a higher-energy orbit to a more stable, lower energy orbit:
energy is emitted in the form of a photon
An electron jumps from the 3rd to the 4th energy level of an atom. What can we assume about this atom?
This atom absorbed a photon that was less than the energy gap between n=3 and n=4.
When the photon is absorbed, the electron jumps to the next energy level only if the photon's energy is _______________ the gap between the energy levels.
equal to
Which of the following describes the Bohr model?
a small positively charged nucleus with electrons in orbit at different levels
The further an electron is from the nucleus, the ____________ energy it has.
more
In Bohr's model, the energy of a photon absorbed or emitted by the electron will be equal to:
the difference in orbital energies associated with the transition
The model for the atom that was understood when Bohr made his contributions was called the:
planetary model
The principal quantum number, n, corresponds to:
the energy level of the electron
How many orbitals are in the subshell with the following quantum numbers: n=4,l=2,ml=?2,?1,0,1,2?
l=2 and ml=?2,?1,0,1,2 indicate five possible orbitals in the subshell.
The ________ states that no two electrons in the same atom can have exactly the same set of all four quantum numbers.
Pauli Exclusion Principle
The wavefunction is represented by the Greek letter:
psi, ?
The probability of a quantum particle being at a certain location in space is described by:
?^2
In Schrodinger's equation (H? ?=E?), what does H? represent?
set of mathematical operations representing the total energy of the particle
The Schr�dinger equation was developed directly from the:
de Broglie relation
Which of the following can be used to determine the distribution of the electron density with respect to the nucleus?
wavefunctions
the Schr�dinger equation can be written as:
H? ?=E?
The Schr�dinger equation relies on which of the following principles?
the wave-like character of electrons
In Schr�dinger's equation (H? ?=E?), what does E represent?
the actual total energy of the particle
________________ is a form of electromagnetic radiation.
Visible light
Who developed the theory of electromagnetic radiation?
Maxwell
The current view proposes that light is:
composed of both waves and particles (wave-particle duality)
Maxwell's theory of electromagnetic radiation discredited ..
the particle view of light.
What does a wave transport?
energy
Newton
performed experiments with lenses and prisms and was able to demonstrate that white light consists of the individual colors of the rainbow combined together
Huygens
had shown that optical phenomena such as reflection and refraction could be equally well explained in terms of light travelling as high-speed waves through a medium called "luminiferous aether
Thomas Young
demonstrated that light passing through narrow, closely spaced slits produced interference patterns that could not be explained in terms of Newtonian particles but could be easily explained in terms of waves.
James Clerk Maxwel
developed his theory of electromagnetic radiation and showed that light was the visible part of a vast spectrum of electromagnetic waves, the particle view of light became thoroughly discredited.
By the end of the nineteenth century, scientists viewed the physical universe as roughly comprising two separate domains:
matter composed of particles moving according to Newton's laws of motion, and
electromagnetic radiation consisting of waves governed by Maxwell's equations
wave
an oscillation or periodic movement that transports energy from one point in space to another
_____________ are a type of radiation, but not electromagnetic radiation.
Beta rays
A _______ is an oscillation that can transport energy from one point to another.
wave
A wave can transfer ________ without transferring _________.
energy; matter
The realm of physics that described light as having strictly wave-like character is called:
classical electrodynamics
For an atom, electrostatic potential is also called:
Coulomb potential
Bohr used an electron moving in a circular orbit about a nucleus to describe __________________
the model of a hydrogen atom
According to Bohr's model, when does an electron emit electromagnetic radiation?
when it is changing from an orbit of higher energy to a lower one
the principal quantum number
(n)
-designates the principal electron shell
-because n describes the most probable distance of the electrons from the nucleus, the larger the number n is, the farther the electron is from the nucleus, the larger the size of the orbital, and the larger th
the orbital angular momentum quantum number
(l)
-determines the shape of an orbital, and therefore the angular distribution.
-each value of l indicates a specific s, p, d, f subshell (each unique in shape.) The value of l is dependent on the principal quantum number n.
-Unlike n, the value of l can
the magnetic quantum number
(m sub l)
-determines the number of orbitals and their orientation within a subshell
-its value depends on the orbital angular momentum quantum number
-is an interval ranging from -l to +l , so it can be zero, a negative integer, or a positive integer.
the electron spin quantum number
(m sub s)
- does not depend on another quantum number
-designates the direction of the electron spin and may have a spin of +1/2, represented by?, or -1/2, represented by ?.
-when ms is positive the electron has an upward spin, which can be referred to as
When n = 1..
0
when n=2...
l= 0, 1 (l takes on two values and thus there are two possible subshells)
when n=3..
l= 0, 1, 2 (l takes on three values and thus there are three possible subshells)
Principal shell with n = 1 has _______ subshell(s)
one
Principal shell with n = 2 has _______ subshell(s)
two
Principal shell with n = 3 has _______ subshell(s)
three
s subshell
l=0
p subshell
l=1
d subshell
l=2
f subshell
l=3
s orbitals
l=0, ml=0
1 orbital
p orbitals
l=1, ml=-1,0,1
3 orbitals
d orbitals
l=2, ml= -2, -1, 0, 1, 2
5 orbitals
f orbitals
l=3, ml=-3,-2,-1,0,1,2,3
7 orbitals
Pauli Exclusion Principle:
no two electrons can have the same values for n, l, ml, and ms. Although the first three quantum numbers identify a specific orbital and may have the same values, the fourth is significant and must have opposite spins.
Hund's Rule:
electrons fill orbitals one at a time. This means that when drawing electron configurations using the model with the arrows, you must fill each shell with one electron each before starting to pair them up.
Heisenberg Uncertainty Principle:
we cannot precisely measure the momentum and position of an electron at the same time.
As the momentum of the electron is more and more certain, the position of the electron becomes less certain, and vice versa
The phenomenon in which electrons that are closer to the nucleus slightly repel those that are farther out is known as:
shielding