Study Sheet for Chapter 2 Honors Biology
EXTENDED RESPONSE TIPS: EXAMPLE: Surface tension caused by the pulling in of H-bonds of the water molecules. This creates a “film” on the surface of the water. This allows small insects to walk on the surface of water.
#1 Formula = abbreviation of a compound Molecule = 2 or more atoms chemically bonded (can be same or different) Atom = 1 unit – smallest unit of an element Formula = abbreviation of a compound Compound = 2 or more different elements bonded together chemically Symbol = abbreviation of an element Element = 1 kind of substance that cannot be broken down by chemical means – listed on Periodic table
#2 59 Co 27 Mass number = 59 Atomic number = 27 Number of protons = 27 Number of electrons = 27 Number of neutrons = 32
#3 Trace elements Appear in very small amounts Milligrams (mg)
#4 Radioactive isotope Breaks down spontaneously (gives off energy and particles, can be detected on a PET scan) Break down to their more stable form EX: C-14 to C-12
#5 Why do atoms join to form compounds? TO FILL THEIR OUTER ELECTRON SHELL
#6 IONS and ISOTOPES IONS = differ in the number of electrons (charged atoms) ISOTOPES = differ in the number of neutrons (different mass numbers)
#7 Electrons in covalent and ionic bonds COVALENT = electrons are shared IONIC = electrons are transferred (lost/gained)
#8 Solute and solvent and solution Water = solvent – does the dissolving (larger amount) Sugar = solute –being dissolved Both = solution
#9 H-bonding When water reaches 4oC and below H-bonds form an open lattice (less dense) For surface tension, H-bonds pull the water molecules inward to form a “film”
#10 IN ORDER (strongest to weakest): COVALENT IONIC H-bonding Van der Waals
#11 Buffers Minimize the change in pH by adding extra H+ and OH-
#12 ACIDS put H+ ions into solution (H+ donors) BASES put OH- ions into solution (OH- donors)
#13 Water has high heat of vaporization (slow to heat and also slow to cool) So the coastal area temperatures would change less rapidly than inland areas
#14 Strong 1-3 Weak 4-6 pH 3 = [H+] 10-3 ACIDS BASES Strong 1-3 Weak 4-6 pH 3 = [H+] 10-3 pH 4 is 100 X’s the H+ ions than pH 6 Strong 11-14 Weak 8-10 pH 11 = 10-11
#15 Electrons fill 2 8
#16 ACID PRECIPITATION pH lower than 5.2
#17 COVALENT BONDS
#18 H+ ions surround Cl- OH- ions surround Na+
#19 REACTANTS PRODUCTS Left of arrow right of arrow
#20
#20 Elements that are located in the same column behave more alike chemically
#21 Polar Covalent = unequal sharing of e- Nonpolar Covalent = equal sharing of e-
#22 Bohr Model
#23 H-H O-H NaCl
#24 UNIQUE PROPERTIES OF WATER 1. H-bonding 2. Polarity
#25 C H O N Trace element in mg
#25 Fe I F used to prevent tooth decay Used by RBC to carry oxygen in hemoglobin I used to prevent blindness and have proper use of thyroid F used to prevent tooth decay
#26 Elements have different numbers of protons Elements have different numbers of electrons (form different ions and different bonds)
#26 Same column have same outer shell (valence) electrons
#27 ISOTOPES OF AN ELEMENT Same number of protons (same atomic number) Different number of neutrons (different mass number)
#28 Valence electrons (fill inner shell first) 2 8
#29 If atomic number 8 Can form two more bonds
#30 BOTH INTERMOLECULAR Van der Waals = are momentary very weak forces of attraction between nonpolar molecules resulting from uneven electron distributions (EX: gecko hairs on feet and glass) H-bonding = forces between H and F, O, or N
#31 Cations = (+) ions Anions = (-) ions
#32 You need to break the H-bonds to vaporize (form a gas)- takes extra time You need to form H-bonds to form ice – takes extra time
#33
Determine the pH If [H+] = 10-4 = pH 4 [OH-] = 10-10
#34 Mg-2 Cl- K+ I- Ca+2 P-3
#35 Ca = calcium C = carbon Co = cobalt REVIEW YOUR ELEMENTS AND SYMBOLS: Ca = calcium C = carbon Co = cobalt
#36 EXAMPLE Why water makes a nice drop on wax paper: Surface tension on the water. Strong cohesion of the water molecules Weak adhesion to the wax paper. Review blue sheet, water properties quiz and lab.