front 1 Identify the four elements that make up 96% of living matter. | back 1 Oxygen, Carbon, hydrogen, nitrogen. |
front 2 Trace element | back 2 Required by by an organism in only minute quantities Ex: In vertebrates animals with backbone, the element iodine is an essential ingredient of hormones produce by the thyroid gland. |
front 3 Neutron | back 3 electrically neutral |
front 4 Proton | back 4 one unit of positive charge |
front 5 electron | back 5 one unit of negative charged |
front 6 Atomic Number | back 6 Atomic number is only the number of protons in the nucleus of the atom, giving the atom it's identity as a particular element |
front 7 Mass number | back 7 Mass number is the total number of protons and neutrons in the most common isotope of an atom |
front 8 Atomic Mass and weight | back 8 Mass number is an absolute -- it is the total number of protons and
neutrons in an atom |
front 9 How can a atomic number and mass number of an atom can be used to determine the number of neutrons? | back 9 Subtract atomic number from mass number and you will have the number of neutrons |
front 10 How to Isotopes of an element are similar. How the are different. | back 10 The two isotopes of an element have the same number of protons but different numbers of neutrons |
front 11 Describe a biological application that uses radioactive isotopes. | back 11 Certain kidney disorders are diagnose by injecting small dose of radioactively-labled substance into the blood and then analyzing the tracer molecules excreted in the urine. |
front 12 energy | back 12 Capacity to cause change |
front 13 Potential Energy | back 13 energy that matter has because of its ability to make energy (location or structure) |
front 14 Why electrons in the first electron shell have less potential energy that electrons in higher electron shells? | back 14 The frist electron shells looses energy and has the lowest potential energy. the higher electron shell gains energy and it has more potential energy. |
front 15 Nonpolar covalent bonds | back 15 Sharing two atoms. The atoms share the electrons equally. |
front 16 polar covalent bond | back 16 one atom is more electronegative and the atoms do not share the electron equally Ex: Bonds between oxygen and hydrogen atoms of a water molecule are quite polar. A polar covalent bond is a chemical bond where the shared electrons spend more time closer to the nucleus of the more electronegative atom. |
front 17 ionic bonds | back 17 Attraction between an anion and cation. in an ionic bond, the electrons are completely transferred from one atom to another rather than shared. |
front 18 Cation | back 18 positively charged ion. |
front 19 Anion | back 19 negatively charged ion. |
front 20 Why are strong covalent bonds and weak bonds essential in living organisms? | back 20 Strong covalent bonds are needed for living organisms so that
organism bodies can form and hold together and not fall
apart. |
front 21 Hydrogen Bonds | back 21 from when a hydrogen atom covalently bonded to one electronegative atom is also attracted to another electronegative atom. In living cells the electronegative partners are usually oxygen and nitrogen atoms. |
front 22 Van der Waals interactions | back 22 are attraction between molecules that are closer together as a results of these charges |
front 23 How a molecules shape can determine its biological function. | back 23 Shape is determine by position of the atoms orbital, in a covalent bond the s and p orbitals may hybridize creating specific molecule shapes. Molecules shapes is crucial in biology because it determines how biology molecules specifically recognize and respond to one another. The shape they make is called tetrahedron. |
front 24 What is meant by chemical equilibrium? | back 24 When is reached when the forward and reverse reaction occurs at the same rate. |
front 25 reactants | back 25 the staring molecule of a chemical reaction |
front 26 products | back 26 final molecule od chemical reaction. |
front 27 What is the difference between a compound and a molecule? | back 27 Chemical bond = molecule 1 A molecule consists of two more atoms, which can be the same or
different types of atom, that are linked by a chemical bond. A
molecule of H2 or O2 is still a molecule, but not a compound. |