Anatomy Chapter 2 Flashcards TEST 2
About this set
Created by:
degrassiaddict43 on September 27, 2011
Subjects:
Log in to favorite or report as inappropriate.
Order by
50 terms
Terms | Definitions |
|---|---|
 matter | is anything with mass that occupies space. It exists in three major forms: solids, liquids, and gases. |
| solids | have a definite shape and volume and are not compressible. |
| liquids | have a set volume but not set shape. They take the shape of the container they're in and are not compressible. |
| gases | have no set shape or volume. They expand in all directions to fill the container they're in and they are compressible |
| energy | is the ability to do work. It can only be measured through its effects on matter. |
| chemical energy | is stored in the bonds between atoms in molecules. They can release this energy if the molecules are broken down, like food in your stomach. |
| electrical energy | happens through the movement of charged particles. This is what happens in nerves and contracting muscles. |
| mechanical energy | is the direct movement of matter. The heart's pumping of blood is an example. |
| radiant energy | travels in waves. The electromagnetic spectrum includes x-rays, gamma rays, ultraviolet, visible light, infrared, and radio waves. |
| elements | are substances that cannot be broken down further through normal chemical means. Most Chemistry labs have a periodic table showing the 110 or so elements known to humans. Each element has its own symbol. |
| atoms | are the smallest unit of an element that still retains its properties. |
| 4 most common elements (name, symbol, mass %, role) | Oxygen, O, 65.0%, in water and necessary for energy Carbon, C, 18.5%, in all organic compounds Hydrogen, H, 9.5%, in water and most compounds Nitrogen, N, 3.2%, in most protein, DNA, and RNA |
| protons | are positively charged and are found in the center of the atom. |
| neutrons | have no charge and are found in the center of the atom |
| electrons | have a negative charge and are found far from the center of the atom, in a negatively charged cloud, the electrons with less energy being closer to the nucleus. |
| nucleus | is where the protons and neutrons are packed together. |
| planetary model | portrays the nucleus like the sun with the electrons orbiting like planets. |
| orbital model | portrays the electrons in a vague negatively charged cloud, where the electrons are LIKELY to be found. |
| atomic number | is the NUMBER OF PROTONS which determines the identity of the element. ex. Hydrogen is the 1st element because it has 1 proton; Helium is the 2nd because it has 2 protons. |
| atomic mass number | is the combined mass of PROTONS AND NEUTRONS (# of p + # of n). ex. Hydrogen has one proton for a mass of 1; Helium has 2 protons and 2 neutrons for a mass of 4. |
| atomic weight | is the average of all the atomic masses of atoms of a particular element. ex. Carbon has an AW of 12.011 because most carbon atoms are Carbon-12 with an AM of 12, but a few other carbon atoms exist, like Carbon-14 with an AM of 14 |
| isotopes | are atoms of the same element with different numbers of neutrons. ex. Hydrogen, deuterium, and tritium all have 1 proton, but 0, 1, and 2 neutrons respectively. |
| molecule | is made of 2 or more atoms SHARING electrons. They do this to stabilize their electron arrangements. |
| compound | is made of several different types of atoms. ex. NaCl is a compound but H2 is an element. |
| chemical reaction | is when atoms combine or break from other atoms. All normal chemical reactions involve electrons. Electrons exist in certain regions of space around the nucleus called shells or orbitals. Each shell can hold a certain number of electrons. When the lowermost electron shell is filled, then the next one begins to fill. (2, 10, 18) |
| noble gases | most chemical reactions happen because most elements want to make the outmost shell(valence shell) either completely full or completely empty of electrons. Only the noble gases (helium, neon, argon, krypton, xenon, and radon) have a valence shell completely filled and are therefore more stable. So much that they rarely react with anything else. |
| chemical bonds | are forces that hold atoms together, involving electrons in the valence shells. There are three major types: ionic, covalent, and hydrogen |
| ionic bond | is when an atoms GIVES electrons to another atom. Both atoms now have charges (1 positive/ 1 negative) and are known as IONS. This is because the number of electrons and protons is no longer the same in the ion. |
| cations | the atoms that give away electrons form POSITIVE charged ions because they have LESS electrons than protons. ex. NA gives an electron to Cl and they become the ions Na+ Cl- |
| anions | the atoms that receive electrons form NEGATIVELY charged ions because they have MORE electrons than protons. ex. Na gives an electron to Cl and they become the ions Na+ and Cl- |
| attraction of ions | if left as a solid, ions of opposite charge become attracted to each other. The attraction of anions and cations holds the substance together in an ionic bond. |
| electrolyte | if ions are dissolved in liquid, the ions spread out evenly, forming an electrolyte. Electrolytes can conduct electricity. They are also important in living things, especially in nerve cells. |
| covalent bond | is when two atoms SHARE electrons. Such atoms want to fill their valence shell so it has the same number of electrons as the nearest noble gas. |
| single bond | is when two atoms each give up one electron, allowing them to share one pair of electrons between them. ex. H2 |
| double bond | is when two atoms each give up two electrons, allowing them to share two pairs of electrons between them. ex. O2 |
| triple bond | is when two atoms each give up three electrons, allowing them to share three pairs of electrons between them. ex. N2 |
| polar bonds | are when an electron is pulled closer to one end of a covalent bond than the other. ex. H20. Water is polar, which means that it has unique properties when other molecules are dissolved in it. H- slightly positive; O- slightly negative. |
| nonpolar bonds | are when the electrons shared are equally far from both atoms in a covalent bond. |
| hydrogen bond | is when the positive end of one atom is attracted to the negative end of a different atom. |
| synthesis reactions | are when two smaller parts join to make something larger. They are endothermic reactions (absorb energy). A + B ----> AB ex. Amino Acids yields Protein Molecules |
| decomposition reactions | are when a large substance breaks down into smaller pieces. They are exothermic reactions (release heat). AB ----> A + B ex. Glycogen yields Glucose Molecules |
| exchange reactions | are when two substances trade parts. AB + C ----> A + BC = Single Replacement ex. Glucose + Adenosine triphosphate yields Glucose phosphate + adenosine diphosphate AB + CD ----> AD + CB = Double Replacement |
| organic chemistry | molecules contain carbon. Organic compounds are common to living organisms. |
| inorganic chemistry | molecules rarely contain carbon, except for CO2. Other inorganic molecules are: salts, acids, bases. |
| carbon | carbon is well suited for building with since it has four electrons in the valence shell. This means it has to get four electrons to be satisfied. Carbon can form four single bonds or any combination of single, double, and triple bonds that add up to four. No other class of elements is so versatile. |
| ionization | is the process that forms ions. |
| dissociation | is ionization by a molecules fragmenting into smaller ions. All acids and bases dissociate into ions. |
| acids | dissociate into hydrogen (H+) ions and anions ex. HCL ----> H+ + Cl- |
| bases | dissociate into hydroxide (OH-) ions and cations. ex. NaOH ----> Na+ + OH- |
| salts | dissociate into ions, but not H+ or OH-. ex. KCL ----> K+ + Cl- |
First Time Here?
Welcome to Quizlet, a fun, free place to study. Try these flashcards, find others to study, or make your own.