Level 1
What is an atom?
The smallest particle that has all the properties of an element.
What is the building block of matter
Atom
What determines the chemical properties of an element?
The arrangements of electrons in the outermost shells
What is the K shell and how many electrons does it have?
-inner most electron shell
-2 electrons
Atoms of various elements may combine to form structures called _____
Molecules
What is mass?
The quantity of matter in an object
What are the 3 fundamental particles of an atom and what are their charges?
-electron (negative)
-proton (positive)
-neutron (neutral)
Which type of energy is the least familiar, yet the most important in Radiology?
Electromagnetic energy
A Photon is
Any quantum of electromagnetic radiation, it has no mass and no charge
What are the levels of organization for matter?
Atoms combine to make molecules and molecules combine to make tissues
What are the 4 types of atoms?
-Greek
-Dalton
-Thomson
-Bohr
No outer shell can contain more than ____ electrons
8
What is the letter/symbol for atomic number and what does it equal?
(Z) = # of protons
The strength of attachment of an electron to the nucleus is called the _____
Electron binding energy
What is the force that keeps an electron in orbit is
Centripetal force
Who developed the concept of the atom as a miniature solar system?
Niels Bohr
What is tissue made up of?
-matter
-atoms
-molecules
What is the chemical symbol W? What is the atomic number of W?
Tungsten, 74
Can atoms be ionized by changing the number of positive charges?
NO, positive charges (protons) don’t move; they are confined to the nucleus
As atoms get _____ electrons in a given shell become more _______.
bigger, tightly bound
What is matter and what is matter composed of?
Substance that makes up all physical objects or occupies space
Matter is composed of atoms and molecules
When energy is emitted and transferred through matter it is called…
What is the atomic number for tissue and bone?
Soft tissue (#7.4)
Bone (#13.8)
What is a form of electromagnetic radiation, similar to light but of shorter wavelength and capable of penetrating solids and of ionizing gasses.
X-rays
What is radioactivity?
The spontaneous emission of particles and energy in order to become stable.