Chap 7 gen chem.
Wave-particle duality
- All matter exhibits wavelike motion. - Energy and mass can be interconverted. - Matter and energy are different forms of the same entity.
Describe the Bohr model of the hydrogen atom.
- Each energy state of the hydrogen atom is associated with a fixed circular orbit of the electron around the nucleus. - The atom is in its lowest energy states when the electron is in the orbits closest to the nucleus. - Only certain energy levels are allowed within the hydrogen atom.
Describe photons
- Each photon has a specific energy, frequency, and wavelength. - Photons are particles of electromagnetic radiation. - A photon can transfer momentum to another particle in a collision.
Why are electrons restricted to certain, discrete energy levels within an atom?
- Electrons have wavelike motion and are restricted to certain energy states associated with specific wavelengths.
3,0,0 3,1,0 4,2,2 4,1,-1
- an electron in a 3s - and electron in 3p - an electron in 4d - an electron in 4p
quantum number n with reference to the Bohr model of the hydrogen atom?
- an electron with n=2 is at higher energy than an electron with n=1 - n can have any positive, whole-number value greater than equal to 1. - n indicates the energy level of an electron in the atom.
The ______ momentum quantum number has a symbol I and can take values from _______ to (n-1). This number is related to the _____ of the orbital.
- angular - 0 - shape
An orbital with I = 2 is called a ______ orbital. These orbitals always occur in groups of _______ orbitals of equal energy.
- d - 5
Using the Schrodinger wave equation we can determine the probability of finding an electron in particular region of the atom. The probability density ____ with distance from the nucleus, meaning that the farther one gets from the nucleus the _____ likely it is to find an electron. (no electrons in nucleus)
- decreases - Less
In Bohr's model of the atom, the quantum number is associated with the ____ of an electron orbit. the lower the n value, the ____ the electron is to/from the nucleus and the ____ the energy level.
- energy - closer - lower
A central concept in quantum mechanics is that both matter and ____ are alternate forms of the same entity and therefore both exhibit dual characteristics of particles and of _____. This model allows a better understanding of the behavior of tiny particles such as electrons.
- energy - waves
Electrons, like all other matter, exhibit the dual behavior of both ________ and waves. Since electrons travel like waves their energy is restricted to certain energy ___________, each of which is associated with a specific wavelength.
- particles - levels
Electromagnetic radiation consists of particles called _____ , which exhibit both and ______ particle behavior. The greater the momentum of a photon, the _____ shorter its wavelength
- photons - wave - shorter
Heisenberg's uncertainty principles states that it is not possible to know the exact momentum and ___________ of a particle simultaneously. In therms of atomic structure, this means that we cannot determine fixed ____________ of electrons but can only determine the _________of finding an electron in a given region of space.
- position - orbits - probability
The angular momentum quantum number, I, indicates the ____ of the orbitals in an atom. A value f I = 0 indicates a(n) _____ type orbital while a d orbital is indicated by an I value of _____.
- sublevel - s - 2
Which of the following statements correctly describe the magnetic quantum number, m₁?
- the allowed values of m range from -1 to +1 - This value indicates the orientation of an orbital in the space around the nucleus.
Which of the following statements correctly describe the info provided by quantum numbers.
- the quantum number "n" indicates the principle energy level of an orbital. - the quantum number "l" indicated the shape of an orbital. - the relative size of the orbital is indicated by the value of "n".
a "p" orbital has _______ regions or lobes of high electron probability, on either side of the nucleus. This gives the orbital a dumbbell shape with a(n) _______ or region of zero electron density at the nucleus.
- two - nodal plane
All matter behaves as though it moves in a(n) ______. The motion of any particle can be described by the de Broglie equation, which relates the wavelength of a particle to its _______ and speed.
- wave - mass
In the quantum mechanical model of the atom, and electron is viewed as a wave-particle that occupies a three-dimensional space near the nucleus. The movement of the electron is described by a ________ function, which is also called an atomic _____________.
- wave - orbital
Which of the following statements correctly describe the principle quantum number, n?
-the higher the value of "n", the higher the energy level. -The lower the value of "n", the greater the probability that the electron is closer to the nucleus. -"n" can have any positive whole-number value - indicates relative size of the orbital and there the relative distance from the nucleus of the peak in the radial probability distribution plot.
sets of quantum numbers are allowed?
2,1,-1 1,0,0
Which of the following correctly defines an atomic orbital in terms of the quantum mechanical model of the atom?
A mathematical function that describes the position of the electron-wave in three dimensions.
Which of the following defines the ground state of an atom?
When electron is in the first orbit- closest to the nucleus, and the H atom is in its lowest (first)
m indicates
orientation of an orbital in space
n indicates
principle energy level
An orbital with I = 0 is called a(n) _____ type orbital and has a(n) _______ shape. There is always a total of ______ orbital(s) of this type for each principle energy level.
s, spherical, 1Whi
l indicates
sublevel of the orbital
Why does each element have its own unique atomic line spectrum?
the lines in the spectrum correspond to the differences btwn the specific energy states in the atom.
The shape of the orbital is related to the value of.
the quantum number "l"
relative size of the orbital is related to the value of
the quantum number "n"