Download Honors Chemistry

Honors Chemistry
Name _________________________________
Chapter 4: Review Worksheet
Date _____/_____/_____
Period _____
1. A rock radio station broadcast at 102.5 MHz, how much energy is used to produce that
frequency?
E = h
E = (6.626 x 10-34 J ▪ sec)(1.025 x 108 Hz)
= 6.792 x 10-26 J
2. Label the parts of the electromagnetic spectrum, including the parts of the spectrum that we
can see, and the change in wavelength, frequency and energy that occurs on the spectrum.
700nm
400nm
ROYGBIV
Radio
Waves
Microwaves
Infrared
Radiation
Visible
Light
Ultraviolet
Radiation
x-rays
Gamma
Rays
Wavelength () decreases
Frequency () increases
Energy (E) increases
3. What does it mean when it is stated that an electron is in its ground state?
The statement indicates that the electron is in the lowest available energy state of the
atom.
4. What does it mean when it is stated that an electron is in an excited state?
The statement indicates that the electron has absorbed energy and moved out further
away from the nucleus (into a higher energy level). The absorption of energy gives the
electron a higher potential energy than it had in the ground state.
5. What type of energy causes an electron to move from its ground state to an excited state?
The energy has to be a high level of energy. The two types of energy that we will observe
in the lab are electrical energy and heat energy.
6. How is the length of a wave determined?
Wavelength is determined by measuring the distance between corresponding points on
adjacent waves (crest to crest or trough to trough).
7. What is a quanta of energy, as described by Max Planck? What is a quantum of
electromagnetic radiation called?
A quanta of energy is the minimum quantity of energy that can be lost or gained by an
atom.
A quantum of electromagnetic energy is called a photon.
8. What is a line-emission spectrum and how is it different from a continuous spectrum?
A line-emission spectrum is emitted light that gives off separated frequencies of
electromagnetic radiation when passed through a prism.
A continues spectrum is an emission of a continuous range of frequency of
electromagnetic radiation.
9. What causes the production of a line-emission spectrum?
Spectral lines are produced from the emissions (or release) of particular frequencies of
radiation. These particular frequencies of energy are the difference between where the
electron ended up after absorbing energy and the electrons ground state.
10. What is meant by an electron having dual wave-particle nature, where were these
electrons described as being located, and who suggested this theory?
Sometimes light acts like a wave and some other times like a particle. To understand
what light is one must take both characteristics into consideration. Neither the theory of
particles (photons) nor the wave theory of light is correct if considered alone. Only
combined does one get a full and proper understanding.
11. What is the Heisenberg uncertainty principle?
It is impossible to determine simultaneously both the position and velocity of an electron
or any other particle.
12. What does each of the following indicate?
Spin Quantum number – has only two possible values (+½ , – ½ ) – which indicates
the two fundamental spin states of an electron in an orbital.
Angular Quantum number – indicates the shape of the orbital. It has integral values
from 0 to n – 1 for each value of n and is the same as the
sublevel.
Principle Quantum number – indicates the main energy level occupied by the
electron. It has integral values of 1, 2, 3, … and is the
same as the level.
Magnetic Quantum number – indicates the orientation of an orbital around the
nucleus. It has integral values of – to , including
zero, and is the same as the orbital.