Term
| What is the difference between an atom and an ion? Give an example of each. |
|
Definition
An atom is the smallest particle that retains properties of a substance. (Ex. Hyrdrogen)
An Ion is an atom w/ a charge (+/-) and the protons and electrons are unbalanced. (ex. Al3+) |
|
|
Term
| What is the difference between atomic number and atomic mass? |
|
Definition
| The atomic # is the # of protons. The atomic mass is the average mass of all the atoms and isotopes of an element. |
|
|
Term
| What is the difference between a mass number and atomic mass? |
|
Definition
| The mass # is not on the periodic table, it's the # of protons + the # of neutrons. Atomic mass is the average mass of all the atoms and isotopes of an element. |
|
|
Term
|
Definition
| A group of the same element where each has a different # of neutrons |
|
|
Term
Protons, neutrons, electrons?
73Ge, 85Rb+, 16N3- |
|
Definition
a. P=32 E=32 N=41
b. P=37 E=36 N=48
c. P=7 E=10 N=9 |
|
|
Term
| What is radioactivity? Provide example. |
|
Definition
| Spontaneous emission of radiation by an unstable atomic nucleus. Ex. Carbon-14 |
|
|
Term
|
Definition
a= 4, 2
(symbol is fat looking fish thing)
b= 0, -1
(symbol is B w/ a tail)
g= 0, 0 (symbol is skinny upside down fish) |
|
|
Term
| Explain Rutherfords radioactivity experiment |
|
Definition
| involved shooting a radioactive substance at a radiation detector. There was either a + or a - charge on each side. Some of the substance was attracted to the - charge, so he concluded that it was + charged (alpha), some was attracted to the + charge, so he concluded it was - charged (beta). and some wasn't attracted to either so it had a neutral charge (gamma) |
|
|
Term
| Rutherford's alpha scattering experiment and what it revealed about atoms |
|
Definition
| He shot alpha particles at a very thin sheet of gold foil. Most of the particles went straight through the foil, but a small fraction deflected off of it at very wide angles. He found that the small fraction of the particles bounced off of something very small in the atom. He came to the conclusion that this was a nucleus & only a few particles bounced off of it b/c atoms are made up of mostly empty space. |
|
|
Term
| What two forces act upon a nucleus? |
|
Definition
| electrical force and strong nuclear force |
|
|
Term
| What determines the stability of an atom? |
|
Definition
| the proton to neutron ratio |
|
|
Term
| How are stable isotopes of small atoms different from stable isotopes of lg. atoms? |
|
Definition
| For small atoms to be stable, the number of neutrons should apx. = the number of protons. For lg. atoms, there needs to be more neutrons than protons for it to be stable. |
|
|
Term
| Compare the relative strength of each type of radiation. What material can block each type? |
|
Definition
| Alpha radiation doesn't have much strength and is hardly dangerous unless you eat it. You can block it with paper or clothing. Beta has moderate strength but it can easily be blocked by metal foil. Gamma has the most strength & is very dangerous. You can block it w/ lead or concrete. |
|
|
Term
| What is alpha particle? Beta particle? Gamma radiation? |
|
Definition
A. + charged particle, it has 2 protons and 2 neutrons & is identical to a helium nucleus. Its emitted from certain radioactive nuclei.
B. An electron resulting from the breaking apart of neutrons in an atom.
C. highenergy photon emitted by a radioisotope. |
|
|
Term
|
Definition
| the splitting of a large nucleus into smaller fragments. Ex atomic bomb and nuclear reactors |
|
|
Term
|
Definition
| When nuclei combine to produce a nucleus with a greater mass. Ex. Energy source & hyrdrogen bombs |
|
|
Term
|
Definition
| 1st discovered radioactivity by leaving a piece of pitchblende on a photographic plate. He found that it left a strong, clear image on the plate. It was caused by radiation but he didn't know it at the time. |
|
|
Term
|
Definition
| Was the first to explain radioactivity through numerous experiments. Also she discovered elements radium and pulonium. |
|
|
