Periodic Table, Atoms, Ions, & Molecules Flashcards
Who created the Planetary Model of an atom?
Niel’s Bohr
What is J.J. Thomson’s atomic model?
Plum pudding model
He created the Electron Cloud/Quantum Model of an atom
Erwin Schrodinger
He created the Solid Sphere Model otherwise known as the Billiard Ball Model
John Dalton
What is Ernest Rutherford’s proposed atomic model?
Nuclear Model
Define orbital
It is a region in space where the probability of finding an electron is the highest; It is where you could find electrons moving around/orbiting the nucleus at a lightning pace
It is the function developed by Erwin Schrodinger in his cloud model to describe a cloud-like region where the electron is likely to be found
The probability function
How many electrons can be accommodated in each orbital?
s-orbital: 2
p-orbital: 6
d-orbital: 10
f-orbital: 14
Describe the relationship between the electron configuration and the periodic table
By looking at the electron configuration of an element, specifically at its last electron, we will be able to locate the position of that element in the periodic table.
For example, the last electron of carbon is 2p^2. Therefore, it is located on the second period (based on the coefficient of p), on the second column (based on the superscript of p) of the p-block on the right side of the table.
It also represents the number of electron shells of the element
Period
TRUE or FALSE: Only the representative elements (from Group 1A-8A) have their group numbers also correspond to the number of their valence electrons
TRUE
It states that electrons fill lower-energy atomic orbitals before filling higher-energy ones
Aufbau (building-up) Principle
According to this rule electron pairing in p, d and f orbitals cannot occur until each orbital of a given subshell contains one electron each or is singly occupied.
Hund’s Rule (of Maximum Multiplicity)
It states that no two electrons can have the same set of 4 quantum numbers
Pauli Exclusion Principle
This quantum number tells you the period number / energy level or shell where an atomic orbital can be found.
Principal quantum number
It also describes how far away from the nucleus the shell or energy level under consideration is. The lower the number, the closer the energy level is to the atom’s nucleus.
Principal quantum number
It represents the shape or the kind of sublevel or orbital (spdf) that is being occupied by the electron
Secondary quantum number/Azimuthal quantum number/Angular quantum number
What are the symbols of the four quantum numbers?
(n, l, ml ms)
Enumerate the angular quantum number of each orbital type
s: l = 0
p: l = 1
d: l = 2
f: l = 3
How do we determine the secondary quantum number?
l = n-1
It indicates the kind of suborbital within the sublevel where the electron is found.
Magnetic quantum number
What are the possible values of magnetic quantum numbers for each angular quantum number/sublevel?
0 - 0
1 - -1, 0, +1
2 - -2, -1, 0, +1, +2
3 - -3, -2, -1, 0, +1, +2, +3
Describes the direction (clockwise or counter-clockwise) in which an electron spins
Spin quantum number
Why are +- 1/2 the only possible values for the spin quantum number
Two electrons in one suborbital are given 50% each
Describe the properties of an electron associated with each of the following four quantum numbers: n, l, ml, and ms
n - energy level or how far an electron is from the nucleus (The lower the number, the closer the energy level is to the atom’s nucleus; the closer the electron is to the nucleus, the lower its energy)
l - shape of the orbital (s, p, d, f)
ml - orientation of the orbital with respect to the same l value (i.e. positive or negative)
ms - spin of the electron
What are the atomic properties with periodic trends?
atomic size (radius), ionization energy, electron affinity, electronegativity
Describe the Rules on Filling of Atomic Orbitals
- Aufbau Principle -
- Hund’s Rule of Multiplicity -
- Pauli Exclusion Principle -
It represents the distance of the boundary surrounding the cloud of electrons to the nucleus
Atomic size
It is the number of protons in the nucleus of an atom
Atomic number
It refers to the number of protons and neutrons in an atom
Mass number
It describes the tendency of an atom to attract electrons towards itself
Electronegativity
It is the amount of energy required to remove an electron from an atom/molecule to form a positive ion
Ionization energy
It is the amount of energy released when an electron is added to a neutral atom/molecule to form a negative ion
Electron affinity
What are the atomic radius trends?
LEFT TO RIGHT (ACROSS A PERIOD) - DECREASES
TOP TO BOTTOM (GOING DOWN A GROUP) – INCREASES
Why does the atomic size decrease from left to right within a period?
Because as more electrons are being added to the same shell, more protons are also being added to the nucleus, making it more positively charged. In turn, the nucleus is able to attract more outer electrons and pulls their shells closer to its center
More protons, more effective nuclear charge, and therefore smaller atomic size
What is the periodic trend for ionization energy?
LEFT TO RIGHT (ACROSS A PERIOD) - INCREASES
TOP TO BOTTOM (GOING DOWN A GROUP) - DECREASES
What are the trends for electron affinity?
LEFT TO RIGHT (ACROSS A PERIOD) - INCREASES
TOP TO BOTTOM (GOING DOWN A GROUP) - DECREASES
What are the trends for electronegativity?
LEFT TO RIGHT (ACROSS A PERIOD UNTIL GROUP 7A) - INCREASES
TOP TO BOTTOM (GOING DOWN A GROUP) - DECREASES
Which is more electronegative? metals or non-metals?
Non-metals
What are the 4 natures of matter according to Dalton’s atomic theory?
- Elements are composed of extremely small particles called atoms.
- All atoms of a given element are identical, having the same size, mass, and chemical
properties. The atoms of one element are different from the atoms of all other elements. - Compounds are composed of atoms of more than one element. For any given compound, the atoms present are always in the same ratio.
- A chemical reaction involves only the separation, combination, or rearrangement of atoms; it does not result in the creation or destruction of atoms
According to the law, if two elements can combine to form more than one compound, the masses of one element that combine with a fixed mass of the other element are in ratios of small whole numbers
Law of multiple proportions
It states that different samples of the same compound always contain its constituent elements in the same proportions by
mass
Law of definite proportions
TRUE or FALSE: Neutrons are present in the nucleus of all atoms except hydrogen
TRUE
Atomic number (Z) vs Mass number (A)
Z - # of protons
A - protons + neutrons / Z + neutrons
Protons and neutrons in the nucleus are collectively known as?
Nucleons
These are atoms that have the same Z but different A
Isotopes
He discovered neutrons
James Chadwick
What was the experiment conducted by Robert Millikan that led to the discovery of the charge of an electron?
Oil drop experiment
Who discovered the electron?
JJ Thomson
He did the gold foil experiment that led to the discovery of protons
Ernest Rutherford
He did the gold foil experiment that led to the discovery of protons
Ernest Rutherford
It refers to an atom with a net positive or negative charge
Ion
Atoms that have the same number of protons but different number of neutrons
Isotopes
One of two or more distinct forms of an element
Allotrope
Good conductors of heat and electricity
Metals
Poor conductors of heat and electricity
Non-metals
