Module 2 ( Atomic Theory, Electron Configuration, The Quantum Mechanical Model, The Periodic Table) Flashcards
The scientific description of nature of atoms
Atomic Theory
He came up with the idea that if you continued to cut something, eventually you would end up with something that couldn’t be cut anymore
Democritus
What is an atom?
The smallest particle that an element can be divided and still be the same substance
Atomos means?
cannot be divided
He realized that atoms combine in very specific proportions based on mass
John Dalton (1803)
John Dalton’s model
Solid Sphere Model
On what model indicated that all substances are made of atoms that cannot be created, divided, or destroyed
Dalton’s Solid Sphere Model
Who was the proponent of the Plum Pudding Model and when was it proposed?
J.J Thompson (1897)
What does the plum pudding model indicate?
Electrons are mixed throughout the atom, like a soup or a plum pudding
Who discovered electrons?
J.J Thompson
What did Ernest Rutherford discover in 1909?
He discovered that an atom contains a nucleus with positively charged particles and electrons must be floating around the nucleus
True or False. Rutherford indicates that most of an atom is empty space
(If false, correct the statement)
True
He proposed that electrons move around the nucleus in energy levels but no electrons in between
Niels Bohr (1913)
True or False. According to Bohr, electrons have a tendency to stay only on their corresponding energy levels.
(If false, correct the statement)
False.
Electrons can jump from one level to another.
Who were the proponents of the Modern Atomic Theory?
Erwin Shrodinger and Werner Heisenberg
Modern Atomic Theory indicates that…
Electrons have no predictable pattern and move in a region called the electron cloud.
What does it mean when:
a) protons = electrons
b) protons > electrons
c) protons < electrons
a) an atom has no charge
b) has positive charge
c) has a negative charge
Electrons, protons, and neutrons are called?
Subatomic particles
True or False. Bohr found that “cathode rays” were actually particles travelling from cathode to anode and called them electrons
(If false, correct the statement)
False.
Thompson found that “cathode rays” were actually particles traveling from cathode to anode and called them electrons.
Who discovered neutrons?
James Chadwick (1932)
What charges can be found in the nucleus? Outside the nucleus?
Protons and neutrons in the nucleus.
Electrons are surrounding the nucleus.
It is the number of protons which is also the number of electrons
Atomic number
True or False. The atomic number is unique to each element.
If false, correct the statement
True
What is the mass number?
The sum of protons and neutrons
Enumerate the three nuclei of H isotopes
Protium, Deuterium, and Tritium
It describes how the electrons are distributed in the various atomic orbitals.
Electron configuration
What are the two ways of writing electron configuration
spdf notation, orbital box notation
It states that electrons enter the lowest energy orbitals first.
Aufbau’s Principle
True or False. If the principal quantum number (n) is lower, then the energy level is higher.
(If false, correct the statement)
False.
The lower the n, the lower the energy.
An atomic orbital may only have up to 2 electrons.
Pauli’s Exclusion Principle
Explain Hund’s rule.
It states that in degenerating orbitals, you fill half way first before pairing electrons.
Degenerate orbital means…
they have the same energy
True or False. A similar configuration causes them to behave chemically
(If false, correct the statement)
True
The total number of electrons that can be accommodated in an energy level.
2n^2
The principal quantum number is also known as…
Bohr’s spectral lines
Splitting of Bohr’s spectral lines under a high-resolution spectroscope
Azimuthal quantum number
The azimuthal is also known as…
sub energy levels or orbitals
Values of azimuthal quantum #
0 to n-1
Indicate the energy level when l = 0, 1, 2, 3
0 - s orbital
1 - p orbital
2 - d orbital
3 - f orbital
Splitting of high-resolution lines in a magnetic field
Magnetic quantum number
True or False. The magnetic quantum number is also called angular momentum.
(If false, correct the statement)
True
Values of the magnetic quantum number range from
-l to 0 +l
Spin Quantum Number
Indicates electron spin in the orbital
Values for the spin quantum number
-1/2, +1/2
The area around the nucleus where the probability of finding the electrons are maximum.
Orbitals
Indicate the shapes of each orbital.
s - sphere-shaped
p - dumbbell-shaped
d - double dumbbell-shaped
f - lobbed dumbbell
How many electrons can each orbital hold?
s - 2
p - 6
d - 10
f - 14
Who introduced the 4 initial elements and what are those?
Aristotle
Fire, Water, Air, Earth
This is when 14 elements were known
1700
He wrote the first extensive list of 33 elements.
Antoine Lavoisier
What did Johann Dobereiner found out in 1829?
In a group of three, the average atomic mass of the first and third elements is equal to the atomic mass of the second element.
Who formulated the Law of Triads?
Johann Dobereiner
He arranged the known 62 elements from lightest to heaviest based on increasing atomic weights
John Newlands (1864)
True or False. Mendeleev noticed that every 8th element had similar chemical and physical properties.
(If false, correct the statement)
False.
Newlands noticed that every 8th element had similar chemical and physical properties.
Who is the proponent of the Law of Octaves?
John Newlands
A Russian chemist that organized elements by their atomic mass.
Dmitri Mendeleev (1869)
The Father of Modern Periodic Table
Dmitri Mendeleev
It states that the physical and chemical properties of elements are periodic functions of their atomic weights.
Periodic Law
He arranged elements by atomic number
Henry Moseley
Properties of elements are periodic functions of their atomic number
New Periodic Law
He helped establish noble gases as a new group in the periodic table.
William Ramsay (1904)
What did Ramsay discovered and which is the first?
Noble gases.
Helium and Argon are the first to be discovered.
He discovered 8 new elements and the only living person whom an element was named.
Glenn Seaborg
How many elements are there?
118 elements, 82 naturally occurred on Earth, 36 have been created
Indicate which are period and group in a periodic table.
Period/ series - horizontal rows
Group/ Family - vertical columns
Where are metals, metalloids, and nonmetals located in the periodic table?
Metal - left side
Nonmetals - right side
Metalloid - boundary
The most metallic element
Francium (Fr)
It has the tendency to lose electrons and form cations.
Metals
Good insulators and has a tendency to gain electrons and form anions.
Nonmetals
The most reactive nonmetal
Fluorine
Elements have similar properties due to the similarities in the number of electrons in outer shells
The Group
Two categories of group/family
Group A - Representative elements
Group B - Transition Elements
Horizontal rows are also known as series.
Period
True or False. n is the same as the periodic number.
If false, correct the statement
True
It states that atoms or ions often react to obtain exactly eight electrons in their valence shell.
Octet rule
Group 1A and very reactive in its elemental form.
Alkali Metals
They form compounds with halogens similar to table salt.
Alkali Metals
A very reactive group of elements.
Halogens
What are noble gases?
Group 8 of elements that are very stable and are unreactive gases.
It is half the distance between the nuclei of 2 like atoms.
Atomic Radius
True or False. As you move down the group, the atomic radius decreases. And as you move across, it increases.
(If false, correct the statement)
False.
As you move down, it increases. It decreases as it moves from left to right.
What is ionization energy?
The energy required to remove 1 electron from an atom.
What does it mean when there is low ionization? high ionization?
Low IE - easy to remove the electrons
High IE - hard to remove electrons
True or False. As you move down, ionization decreases. It increases as you move across from left to right,
(If false, correct the statement)
True.
True or False. As you move down, electronegativity decreases. It increases as you move across from left to right,
(If false, correct the statement)
True
The tendency of an element to be shiny, silver, and malleable,
Metallic character
True or False. As you move down, the metallic character decreases. It increases as you move across from left to right,
(If false, correct the statement)
False.
As you move down, the metallic character increases. It decreases as you move across from left to right.
