BIOL 1201: Exam 1 Questions and Answers Graded A+

BIOL 1201: Exam 1 Questions and Answers Graded A+ A substance that cannot be broken down i nto other substances by ordinary chemical procedures is a(n) _____. ✔✔element Organisms are largely composed of __ elements. ✔✔11 About 25 of the 92 natural elements are known to be essential to life. Which four of these 25 elements make up approximately 96% of living matter? ✔✔carbon, hydrogen, nitrogen, and oxygen What determines solubility? ✔✔"like dissolves like" Atom ✔✔Smallest unit of matter that retains all the properties of that element What is the mass and charge of protons? ✔✔Mass: 1 Dalton Charge: +1 What is the mass and charge of neutrons? ✔✔Mass: 1 Dalton No charge What is the mass and charge of electrons ? ✔✔Mass: close to none (about 1/10000 that of a proton or neutron) Charge: -1 Which subatomic particle(s) always have a positive charg e? ✔✔protons Atomic Number ✔✔equal to the number of protons in an atoms In a neutral atom, the atomic number is equal to... ✔✔the number of protons What is the atomic number of an atom that has 6 protons, 6 neutrons, and 6 electrons? ✔✔6 From its atomic number of 15, it is possible to predict that phosphorus always has ___. ✔✔15 protons Atomic Mass ✔✔the sum of the number of protons and neutrons in an atom Fluorine's atomic number is 9 and its atomic mass is 19. How many neutrons does fl uorine have? ✔✔10 neutrons An uncharged atom of boron has an atomic number of 5 and an atomic mass of 11. How many protons does boron have? ✔✔5 protons Changing the number of _____ would change an atom into an atom of a different element. ✔✔protons Isotopes ✔✔variants of an atom that have different atomic masses due to differing numbers of neutrons What refers to atoms with the same atomic number but different atomic masses? ✔✔isotopes True or False: An atom with more neutrons than the atom described i n the question above will have a different valence. ✔✔False Where are protons located within an atom? ✔✔the nucleus Where are neutrons located within an atom? ✔✔the nucleus Where are electrons located within an atom? ✔✔orbitals, or shells, around the nu cleus of an atom What are the names of the first three electron orbitals and how many electrons do each of them contain? ✔✔K-shell: 2 electrons L-shell: 8 electrons M-shell: 8 electrons An atom with the atomic number 9 will have _______ electrons in its outermost electron shell. ✔✔7 Electrons always try to be in the ____ orbital or energy shell. ✔✔lowest