Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
CHM 106
Atoms and radioactivity chapter 2
| Question | Answer |
|---|---|
| Atoms | basic structural units of matter |
| Neutrons | Negatively charged particles. |
| Nucleus | A small dense center that has a positive charge and is surrounded by moving electrons. |
| Protons | Positively charged particles. |
| Electrons | Negatively charged particles. |
| Anions | ions that are negatively charged |
| Cations | ions that are positively charged |
| AMU | unit called the atomic mass unit or AMU is used when discussing Atoms. |
| atomic symbol | a one- or two-letter abbreviation for a chemical element name |
| atomic number | whole number on periodic table that IDs the element |
| atomic mass | number protons plus neutrons |
| Isotope | same element, same number of electrons, same chemical properties different number of neutrons yield a different mass number |
| radioactivity | nuclear radiation energy is given off spontaneously from the nucleus of an atom |
| radioactive decay | isotopes that are not stable become stable by spontaneously emitting radiation from the nuclei |
| radioisotope | isotope that emits radiation uranium trifold is the symbol of radiation |
| alpha particles | represented by the Greek letter A or S4 to helium atoms without electrons carries a plus to charge |
| beta particles | Neutron ejects energy electron -1 charge Neutron becomes proton represented by the Greek letter b |
| gamma rays | high-energy radiation, no particle, unstable nucleus rearranges, higher radiation than x-ray |
| positron | same mass as beta. Plus one charge, unstable nucleus changes proton neutron; Decay process positron collides with electron to emit energy in the form of gamma rays (petscan) |
| alpha decay | always gives up helium |
| effect of half-life | physical Half-Life shortened by biological half life |
| biological Half-Life | the rate of elimination due to bodily processes |
| determining half life | to calculate the remaining amount of sample- equation : remaining Isotopes = (1/2 in) exponent x the start amount (1/2) |
| Millirem | an extremely small measure of energy |
| Sievert (Sv) | the unit for the dose of radiation that affects the human body |
| electron cloud model | a model of an atom in which the atom consists of a small but massive nucleus surrounded by a cloud of rapidly moving electrons. |
| name 3 components of atom | proton, neutron, electron |
| proton weighs | 1 amu |
| neutron weighs | 1 amu |
| electron weighs | 1/2000 of amu |
| ion | charged atom or molecule |
| If a balanced atom loses one or more electrons, it will become a | positively charged cation |
| Alpha particles | Travel- Tissue penetration- stops at the skins surface, dangerous if eaten or inhaled Protection- paper and clothing can protect |
| Beta particles | Travel- a few meters Tissue penetration- will not penetrate past the skin layer Protection- heavy clothing, plastic or aluminum foil |
| gamma | Travel- several hundred yards Tissue penetration- fully penetrates body Protection- thick lead, concrete, layer of water |
| xray | Travel- travel several meters Tissue penetration- penetrates tissues but not bone Protection- lead aprons, concrete barriers can protect |
| ionizing radiation | A type of high-energy radiation that has enough energy to remove an electron (negative particle) from an atom or molecule, causing it to become ionized. Ionizing radiation can cause chemical changes in cells and damage DNA. |
| Alpha decay | occurs when an atom loses two neutrons and two protons The two numbers found on the periodic table will change. The first number, the proton number, will be reduced by two, and the second number, the atomic mass, will be reduced by four. |
| Beta decay | a radioactive decay in which a beta ray is emitted from an atomic nucleus. During beta decay, the proton in the nucleus is transformed into a neutron and vice versa. If a proton is converted to a neutron, it is known as β+ decay. |
| A proton is a subatomic particle having a positive electrical charge (+1). A positron is also a positively charged subatomic particle. | |
| Positron emission | subtype of radioactive decay called beta decay, in which a proton inside a radionuclide nucleus is converted into a neutron while releasing a positron and an electron neutrino |
| gamma decay | type of radioactivity in which some unstable atomic nuclei dissipate excess energy by a spontaneous electromagnetic process |
| Curie | The rate of decay is often referred to as the activity of the isotope and is often measured in Curies (Ci) 1 Ci is equal to 37 billion (3.7 x 10e10) disintegrations per second |
| becquerel (Bq) | SI measure of source strength or total radioactivity, and is defined as one disintegration per second; the units of becquerels are second−1. The decay rate dN/dt is measured in becquerels. |
Created by:
mosciencehelp
Popular Chemistry sets