Intro to General Chemistry Flashcards
Which of the following particles form the nucleus of the atom? Select all that apply.
a) proton
b) neutron
c) electron
proton and neutron
What is the approximate mass of a proton?
a) 1 amu
b) 0 amu
mass of proton = 1 amu
What is the approximate mass of an electron?
a) 1 amu
b) 0 amu
mass of electron = 0 amu
What is the approximate mass of a neutron?
a) 1 amu
b) 0 amu
mass of neutron = 1 amu
What is the atomic number and what is the single letter abbreviation for it?
number of protons
Z
What is the mass number? What is its single letter abbreviation?
number of protons + neutrons
A
What are isotopes?
elements that have the SAME number of PROTONS but DIFFERENT number of NEUTRONS
TRUE or FALSE: Elements of the same period are most likely to react in similar ways.
FALSE –> Elements of the same GROUP are most likely to react in similar ways
What are the 4 quantum numbers and what do they describe?
n = principle quantum number --> energy level and distance from nucleus l = angular momentum quantum number --> orbital shape (s, p, d, f) ml = magnetic quantum number --> orbital orientation (px, py, pz) ms = spin quantum number --> spin of the electron
What are the possible values for each of the quantum numbers?
n = 1, 2, 3, ... l = n-1 ml = -l to +l (e.g. 3 ml values for l = 1) ms = +1/2 (up) or -1/2 (down)
What are the orbital shapes (spdf) for the following l values? What are the n values?
l = 0 l = 1 l = 2
l = 0 --> s --> n = 1 l = 1 --> p --> n = 2 l = 2 --> d --> n = 3
What is the Aufbau principle?
electrons occupy lowest energy level first (e.g. 1s before 2s)
What is Hund’s rule?
electrons will fill all subshells SINGLY before pairing up
What is the Pauli Exclusion Principle?
no 2 electrons in an atom can have the same set of quantum numbers
What is the spdf notation for carbon (C)? Provide both full and abbreviated forms.
full –> 1s^2 2s^2 2p^2
abbreviated –> [He] 2s^2 2p^2
TRUE or FALSE: electrons always lose the outer most (highest n) electrons first.
TRUE
e.g. Co loses one electron…
Co = [Ar] 4s^2 3d^7 –> Co = [Ar] 4s^1 3d^7 [CORRECT]
Co = [Ar] 4s^2 3d^7 –> Co = [Ar] 4s^2 3d^6 [WRONG]
TRUE or FALSE: Electrons can move to different energy levels to fill orbitals in such a way that subshells are half-filled or completely filled.
TRUE –> Half-filled or completely filled subshells are more stable.
What does diamagnetic mean in terms of electron configuration?
all electrons are paired up –> magnetic fields cancel (no net magnetic field)
What does paramagnetic mean in terms of electron configuration?
unpaired electrons present –> NET magnetic field
Metals ___a___ electrons and form _____b_____ to obtain noble gas configuration.
a) lose/gain
b) cation/anion
metals lose electrons –> form cations
Non-metals ___a___ electrons and form _____b_____ to obtain noble gas configuration.
a) lose/gain
b) cation/anion
non-metals gain electrons –> form anions
An ionic bond forms between a/an _____________ and a/an ______________.
metal and non-metal
A covalent bond forms between a/an _____________ and a/an ______________.
non-metal and non-metal
What is the most electronegative atom on the periodic table?
Fluorine
Remember: F O N Cl –> uncle FONCl lol
Why is a cation smaller than an anion?
cation LOSES electrons
anions GAIN electrons
(Remember: if asked about isoelectronic species, the atom with an OVERALL NEGATIVE charge is the largest)
What is lattice energy?
amount of energy required to break apart an ionic lattice
Which rule takes priority in determining greater lattice energy?
a) greater charge
b) smaller radius
a) greater charge
What is ionization energy?
minimum energy required to completely remove an electron from a neutral gaseous atom
TRUE or FALSE: First ionization energy is always greater than the second ionization energy.
FALSE –> 2nd ionization energy is always GREATER
Of the nonradioactive elements, which element has the largest first ionization energy?
a) chlorine
b) fluorine
c) helium
d) neon
c) helium
hint: consider periodic trends
Why is electron affinity always positive for noble gases?
noble gases are stable and REQUIRE energy (endothermic) to gain an electron
Given the velocity and wavelength, what is the formula for frequency?
frequency = velocity / wavelength
TRUE or FALSE: In electromagnetic radiation (EMR), electric and magnetic fields are created parallel to each other and the direction of travel.
FALSE: they are PERPENDICULAR
When EMR (electromagnetic radiation) waves travel in a vacuum, what is its velocity equal to?
speed of light
What is the value for the speed of light?
c = 3 x 10^8 m/s
What is Planck’s equation?
E = hf = hc/wavelength
TRUE or FALSE: short wavelengths are more dangerous than long wavelengths.
TRUE
What is the difference between absorption line spectrum and emission line spectrum?
absorption –> dark lines on light background
emission –> light lines on dark background
What is deBroglie’s postulate? Provide the formula.
wavelength = h/p = h/(mv)
note: h = Planck’s constant, p = momentum
What does the Heisenberg Uncertainty Principle state?
exact position and momentum cannot be measured simultaneously
What did the photoelectric effect (experiment) demonstrate?
particle nature of light
Which of the following are intramolecular bonds? Select all that apply.
a) metallic
b) covalent
c) hydrogen bonding
d) London dispersion forces
e) ionic
f) dipole-dipole
a) metallic
b) covalent
e) ionic
What are the 3 electronegative atoms that can form a hydrogen bond?
F O N
How man hydrogen bonds can one molecule of water form?
4
TRUE or FALSE: molecules that possess an O, N, or F can form hydrogen bonds, yielding low melting and boiling points
FALSE: O, N, F –> HIGH bp and mp
As the number of INTERmolecular forces between molecules ______a______, the boiling point and melting point ______b______.
a) increase/decrease
b) increase/decrease
a) increase
b) increase
or a) decrease b) decrease
List the following from strongest to weakest…use equal sign if equivalent:
dipole-dipole ionic H bonding covalent metallic London dispersion
ionic = covalent = metallic > H-bonding > dipole-dipole > London dispersion
What particle(s) is/are emitted/broken down in alpha decay?
alpha particle (2 protons and 2 neutrons) released
alpha particle = superscript 4, subscript 2, He2+
What particle(s) is/are emitted/broken down in negative beta decay?
neutron –> proton and electron
note: the electron is known as the beta particle
What particle(s) is/are emitted/broken down in gamma decay?
excited nucleus relaxes (energy released)–> gamma rays (high energy photons)
Which type of radioactive decay is most dangerous?
a) alpha decay
b) beta decay
c) gamma decay
c) gamma decay
Define a half-life.
A half-life is the time it takes for half a given sample to decay.
TRUE or FALSE: the half-life of radioactive decay is dependent on time.
FALSE: half-life of radioactive decay is INDEPENDENT of time.
is Mg more or less electronegative than Na
more
does electronegativity increase to the left or right of the periodic table
to the right
if there are more stuff protons, there is ____ of electrons
no shielding or more shielding
more shielding
what is the periodic trend for increasing protons
going from top to bottom, the number of protons increases
what is the Zeff periodic trend and how does it work
it increases downwards and to the right
the more protons there are, the more positive charge acting on the valence electrons, increasing Zeff
the less protons there are, the less positive charge acting on the valence electrons, decreasing Zeff
atomic radius increases from _____ to _____ and from ____ to _____
bottom/top
right/left
top to bottom and right to left
if an atom has more protons than electrons, the size will be greater - true or false, if false, why
false - the size will be smaller because the more protons there are, the greater the electrons will be pulled in, thus the atom will become tighter and smaller
is K + greater in size than Cl- , why or why not
no, because Cl- has fewer protons which mean there is less electron attraction to pull it in smaller
what is the ionization energy periodic trend
it increases to the right and from bottom to top
what is electron affinity
the element’s attraction for electrons
why does Chlorine have a larger electron affinity than potassium
because chlorine needs only one more electron to achieve a full shell, so it has a greater want for the electrons than potassium which would rather lose an electron
