Question | Answer |
What is an atom? | An atom is the building block of all things; it is the smallest particle considered and element |
What are the 3 subatomic particles? What is each's charge? Where are each found? Which ones are denser? | 1. Proton: positive, nucleus, 1. 2. Neutron: neutral, nucleus, 1. 3. Electron: negative, electron cloud, .000000056 (or something like that). |
Why is the # of protons referred to as the ID for the atom? | Because the number of protons is unique to each element. No 2 different elements have the same amount of protons. |
What is a group on the periodic table?
- As you go down a group the number of energy levels ___ and the number of valence electrons ______. | A column of elements
- increases by 1 ; stays the same |
What is a period on the periodic table?
- As you go across a period, the number of energy levels ____ and the number of valence electrons ___. | A row of elements
- stays the same ; increases by 1 |
How is the periodic table arranged? | By atomic number (number of protons). Metals on left, a zigzag of metalloids, then nonmetals on the far right. |
The atomic mass tells us... | the number of protons + neutrons |
The atomic number tell us... | number of protons |
To find the # of protons ... | look at # |
Valence Electrons | The electrons on the outermost energy level |
What does a Bohr diagram show? (Be sure to be able to correctly draw this diagram) | A Bohr diagrams shows all of the electrons in an atom. They are shown in different levels. There are up to 2 electrons on the first, then up to 8 on each following. |
What does a Lewis diagram show? (Be sure to be able to correctly draw this diagram) | A Lewis diagram shows only the valence electrons in an atom, so just the electrons on the outermost energy level. |
How can you quickly and easily tell the number of valence electrons in an atom? | Look at the group that they are in. If they are in the 1st group, they have 1 valence electron. 2nd = 2 v.e. etc. |
What are the two types that we covered? | Ionic and Covalent |
What is Ionic Bonding? | Occurs between a metal and a nonmetal. Metal gives nonmetal electrons. |
What would the charge be of a salt atom that just bonded ionically with an oxygen? (Salt loses an electron) | Na +1 |
What is Covalent bonding?
- Single bond | Two nonmetals share electrons and form a molecule.(Ex: H2O)
- When 1 pair of electrons is shared. |
Subscript | The little number next to an Atomic Symbol indicating how many atoms of an element are in the compound. |
What are ions? | Atoms or groups of atoms that has an electric charge. Neutral atoms loses electron = positively charged ion
Neutral atoms gains electrons = negatively charged ion |
If an atom has 15 protons, 11 neutrons, and 17 electron, what is the atom's electrical charge? | 2- |
The charge of an ion is +2 . Which pair of protons and electrons can represent the ion?
a. 2p, 4e
b. 20p, 18e
c. 73p 70e
d. 80p, 80e | B |
What is an isotope? | An isotope is a variant of an element based on the number of neutrons. |
C-14 is an isotope of Carbon. What does the "14" indicate at the end? | The 14 is the atom's mass. |
What is the difference between Carbon 14 and Carbon 16? | The mass of one is 14 and the other is 16. |
What is radioactive decay? | Radioactive decay is the process in which an unstable, radioactive parent element changes into a stable, nonradioactive daughter element. |
What is a half-life? | A half life is the time it takes for 1/2 of the radioactive element to decay into the daughter element. |
What is carbon14's half-life? | 5,730 years |
What was the first life to inhibit Earth? | Simple, single-celled organisms. From there, the life forms evolved into complex organisms. |
What is the geologic time scale? | Record of the geologic events and evolution/extinction of life forms as shown in the fossil record. |
The longest division of time is called the _____, it took up 88% of Earth's history. | Precambrian. |
The 3 divisions of time after the Precambrian are called and what life forms occupied them (respectively): | 1. Paleozoic (fish) 2. Mesozoic (dinos) 3. Cenozoic (mammals) |
Periods are: | Divisions of time within the eras. (Jurassic) |
Give 3 reasons as to why the fossil record is important. | 1. How life has changed over time - older rocks contain fossils of simpler organisms, younger rocks contain simple + complex
2. What past environments were like
3. How Earth's surface has changed |
What is an ocean current? | Large stream of moving water; like a river within the ocean/ |
How does temperature and salinity affect density? | Cold water is denser than warm. Salt is denser then fresh. |
What is a surface current? What causes it? | A current driven by wind on the surface of the ocean. |
What type of current is the Gulf Stream? Where does it originate? | Surface current. Next to equator. |
How does the Gulf Stream affect climate? | It warms to air around it, and therefore brings warm and rainy climate to Europe and other places it passes. |
Warm air holds more _____ compared to cold air. | Water |
What is the Coriolis effect? What causes it? | The Coriolis effect is the thing that causes currents and winds to take curved patterns. Clockwise = northern hemisphere. Counterclockwise = southern hemisphere. Caused by Earth's rotation |