Chemistry Chp. 7

Match each value of the angular momentum quantum number, to the type of orbital sub-level it designates.

0 = s sub-level 1 = p sub-level 2 = d sub-level 3 = f sub-level

Why is the Bohr model unable to predict atomic line spectra for atoms other than hydrogen?

The Bohr model doesn't take into account electron-electron repulsion in multi-electron systems.

What correctly defines the amplitude of a wave?

The height of each crest or depth of each trough.

What correctly describes the electromagnetic spectrum?

- All waves in the spectrum travel at the same speed in a vacuum. - The color of visible light is related to its frequency.

What describes wave-particle duality?

- Energy and Mass can be inter-converted. - Matter and Energy are different forms of the same entity. - All matter exhibits wavelike motion.

What describes the angular momentum quantum number, l?

- The number of possible l values equals the value of n. - The allowed values of l are determined by the value of n. - The value of l dictates the allowed values of m₁.

Describe the information provided by Quantum numbers?

- The quantum number l indicates the shape of an orbital. - The quantum number n indicates the principal energy level of an orbital. - The relative size of the orbital is indicated by the value of n.

Bohr developed an equation for calculating the energy levels of hydrogen atom. What statements uses this formula?

- The wavelength of a line in the atomic line spectrum for hydrogen. - The difference in energy between two energy levels in a hydrogen atom. - The energy needed to remove an electron completely from the hydrogen atom.

What statements correctly describe probability density and electron probability density diagrams?

- These diagrams show the probability of finding an electron in a particular region of the atom. - The probability density peaks near the nucleus. The probability of finding an electron generally decreases as distance from the nucleus increases.

What describes the limitations of the Rutherford Model of the atom?

- This model couldn't explain why electron didn't emit energy continuously. - This model couldn't explain observed atomic line spectra.

What describes the de Broglie wavelength for a particle?

- Wave behavior is most obvious for very small particles. - The larger the mass of the particle the smaller its wavelength. - The smaller the object, the closer the wavelength is to the size of the object.

What determines the color of visible light?

- Wavelength - Frequency

Describe the principal quantum number, n?

- n can have any positive whole-number value. - The lower the value of n, the greater the probability that the electron is closer to the nucleus.

True or False; The atomic orbital of the quantum mechanical model is very similar to the orbit described by the Bohr model.

False.

The _____ of a wave is the number of wave cycles per second. This quantity is given the symbol v and has s⁻¹ or ____.

Frequency, Hz

The speed of a wave is determined by multiplying the ______ of the wave by its wavelength. In a vacuum all electromagnetic radiation travels at a constant speed, the speed of ________.

Frequency, Light.

An atom is in its lowest energy state, or _______ state, when its electrons are in the lowest possible energy levels. If an electron in the atom absorbs a photon of radiation that's equal in energy to the difference between two energy states it'll move to a higher state and the atom is said to be in the ________ state.

Ground, Excited

What is a consequence of the Heisenberg uncertainty principle?

It isn't possible to assign fixed paths for electron. It isn't possible to determine both speed and location accurately at the same time.

According to the Bohr model for the hydrogen atom, the energy of the atom isn't continuous but has certain discrete energy ________, each of which is related to a fixed circular _____________ of the electron around the nucleus. The farther the electron is from the nucleus, the ________ the energy system.

Levels, Orbit, Higher

Light that consists of a single wavelength or frequency is termed ______, whereas light consisting of many wavelengths is _________.

Mono-chromatic, Poly-chromatic.

The magnetic quanum number has the symbol m₁ and this value indicates the _____ of an orbital in space. The m₁ value is dictated by the value of _____.

Orientation, l.

Electrons, like all other matter, exhibits 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

What describes the s orbital?

- A 2s orbital has two regions of higher electron density. - An s orbital has a spherical shape.

Describe P orbitals?

- A p orbital has a dumbbell shape with two lobes, one on either side of the nucleus. - The p orbitals of a group are perpendicular to each other. - p orbitals always occur in groups of three.

What describes a photon?

- A photon is a particle of electromagnetic radiation. - Matter cannot absorb or emit a fraction of a photon.

What statements describe the behavior of waves and particles according to the "classical" model of matter?

- A wave is able to bend around the edge of an object in its path, whereas a particle is not. - A wave exhibits diffraction patterns, whereas a particle does not.

Match each electron to the set of quantum numbers that could describe it. 3, 0, 0 3, 1, 0 4, 2, 2 4, 1, -1

- An electron in a 3s orbital. - An electron in a 3p orbital. - An electron in a 4d orbital. - An electron in a 4p orbital.

What describes the atom in terms of quantum mechanics?

- Electron exhibits behavior of both waves and particles. - The movement of each electron in the atom can be described by a wave function. - Each electron occupies a 3-d space near the nucleus. This space is described by a wave function.

What is the relationship between energy and frequency?

E = hv h is a constant.

The ______ momentum quantum number has the symbol l and can take values from ______ to (n - 1). This number is related to the _______ of the orbital.

Angular, 0, shape.

Any two waves that meet as they travel through the same medium will interact. If the two waves are in phase their crests will coincide and they will experience _______ interference, producing a wave with a(n) ______ amplitude.

Constructive, Amplitude.

Using the Schrodinger wave equation we can determine the probability of finding an electron in a particular region of the atom. The probability density ________ with distance from the nucleus, meaning that the farther one gets from the nucleus the ________ more likely it is to find an electron (Electrons aren't found within the nucleus).

Decreases, Less.

Atoms, like all other matter, have specific energy levels within them. For an atom to absorb radiation, the energy of the radiation must match the energy ________ between the two energy levels in the atoms.

Difference

What describes the diffraction of light?

Diffraction is the apparent bending of light around the edge of an object in its path.

Visible light and radio waves are both example of _____ radiation, which has a dual nature, possessing the properties of both ______ and waves.

Electromagnetic, Particles.

Why are electrons restricted to certain, discrete energy levels with an atom?

Electrons have wavelike motion and are restricted to certain energy states associated with specific wavelengths.

If a solid object is heated to a high enough temperature it will begin to glow. The color of light it emits depends on the temperature. This relationship between color temperature implies a relationship between _____.

Energy and Frequency.

In Bohr's model of the atom, the quantum number n is associated with the ______ of an electron orbit. The lower the n value, the _____ is to/from the nucleus and the ______ the energy level.

Energy, Closer, Lower

Each element has its own atomic line spectrum, consisting of fine lines of individual wavelengths that are characteristic for the element. This occurs because the atom contains specific ______ levels, and an atom can only or emit radiation that corresponds to the energy _______ between these levels.

Energy, Difference

A central concepts 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.

The phenomenon where an electric current is produced by shining a light on a metal plate is called the ________ effect. The minimum frequency required to cause to flow is called the ________ frequency. This frequency depends on the identity of the metal used.

Photoelectric, Threshold.

Electromagnetic radiation consists of particles called _______, which exhibit both ______ and particle behavior. The greater the momentum of a photon, the ________ its wavelength.

Photon, Wave, Shorter.

Electromagnetic radiation consists of particles called ______, each of which has a discrete amount, or quantum, of energy. However, since electromagnetic radiation also has wave properties, each particle is also characterized by a specific ___________ (m) and frequency (s⁻¹).

Photons, Wavelength

Heisenberg's uncertainty principle stats that's isn't possible to know the exact momentum and _______ of a particle simultaneously. In terms of atomic structure, this means that we can't determine fixed ________ for electrons but can only determine the _________ of finding an electron in a given region of space.

Position, Orbit, Probability.

Match each quantum number to the information it provides. The principal quantum number n indicates the ________. The angular momentum quantum number l indicates the _________. The magnetic quantum number m₁ indicates the ________. The relative size of the orbital is related to the value of ______. the shape of the orbital is related to the value of _________.

Principal energy level. Sub-level of the orbital. Orientation of an orbital in space. The quantum number n. The quantum number l.

Energy isn't continuous, but is quantized or divided into "packets" of which contains a definite amount of energy. An energy "packet" is called a(n) _______ and the energy of each "packet" is directly proportional to its _______.

Quantum, Frequency

When a wave moves from one medium into another at an angle other than 90 degrees the wave will change direction and continue to follow a new straight-line path. This is known as _______, and is responsible for the _______ of white light into its component colors when it passes through a prism.

Refraction, Separation.

All waves in the electromagnetic spectrum travel at the same _____ through a vacuum, but differ in their frequency and wavelength. A wave with a long (large) wavelength will have a ______ frequency.

Speed, Low.

In a photoelectric diode, no current will flow unless light of a certain minimum "threshold" frequency is used. What explains this observation correctly?

The energy of the light photon must match or exceed the energy needed for electrons to break free from the metal.

A p orbital has ____ region 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 Planes.

The Schrodinger wave equation relates the energy of an atom to its electrons in terms of the ____ function of electron. Each solution to the equation represents an allowed ____ state of the atom and is associated with a particular atomic orbital.

Wave, Function.

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, an electron is viewed as a wave-particle that occupies a 3-d space near the nucleus. The movement of the electron is described by a ______ function, which is also called an atomic ________.

Wave, Orbital.

The distance a wave travel during one cycle is called its _____. This is usually measured as the distance between two _______ or two troughs.

Wavelengths, Crest

Types of electromagnetic radiation in order of increasing wavelength (shortest at top to longest at bottom).

X-ray UV radiation Visible Light IR radiation Radiowaves

An orbital with l = 2 is called a _____ orbital. These orbitals always occur in groups of _____ orbitals of equal energy.

d, 5.