Practice Test 1 Bio 103 Name 1) An atom with an atomic number of 9 and a mass number of 19 would have an atomic mass of approximately? a) 10 Daltons b) 19 Daltons c) 9 grams d) 9 Daltons e) 20 grams 2) What is the difference between covalent bonds and ionic bonds? a) Covalent bonds involve the transfer of electrons between atoms, and ionic bonds involve the sharing of neutrons between atoms b) Covalent bonds involve the sharing of protons between atoms, and ionic bonds involve the sharing of neutrons between atoms c) Covalent bonds involve the sharing of neutrons between atoms, and ionic bonds involve the sharing of electrons between atoms d) Covalent bonds involve the sharing of electrons between atoms, and ionic bonds involve the electrical attraction between atoms e) Covalent bonds involve the sharing of protons between atoms, and ionic bonds involve the sharing of electrons between atoms. 3) In ammonium chloride salt (NH 4 Cl) the anion is a single chloride ion, Cl -. What is the cation of NH 4 Cl? a) NH 4 with a charge of +1 b) N, with a charge of +3 c) H, with a charge of +1 d) H 2, with a charge of +4 e) NH 4 with a charge of +4 4) Which of the following explains most specifically the attraction of water molecules to one another? a) Hydrophobic interaction b) Polar covalent bond c) Non polar covalent bond d) Hydrogen bond e) Ionic bond 5) What is the result form an unequal sharing of electrons between atoms? a) A hydrogen bond b) An ionic bond c) A nonpolar covalent bond d) A hydrophobic interaction e) A polar covalent bond
6) What is the maximum number of covalent bonds an element with atomic number 8 can make with hydrogen? a) 1 b) 2 c) 3 d) 4 e) 6 7) Which of the following best describes the relationship between the atoms described below? Atom 1 Atom 2 32 P 15 31 P 15 a) They are both isotopes of phosphorus b) They contain 31 and 32 electrons respectively c) They are both phosphorus cations d) They are both phosphorus anions e) They contain 31 and 32 protons, respectively 8) Which of the following results from a transfer of electron(s) between atoms? a) Polar covalent bond b) Hydrophobic interaction c) Ionic bond d) Hydrogen bond e) Nonpolar covalent bond 9) The atomic number of carbon is 6. Carbon-14 is heavier than Carbon-12 because the atomic nucleus of Carbon-14 contains neutrons. a) 12 b) 7 c) 6 d) 8 e) 14 10) From it atomic number 18, it is possible to predict that the Argon atom had a) 15 neutrons b) 18 neutrons c) 18 electrons d) 18 protons e) C & D only 11) All organisms on your campus make up a) An ecosystem b) A community 2
c) A population d) An experimental group e) A taxonomic domain 12) Which of the following is a trace element? a) Oxygen b) Carbon c) Iron d) Hydrogen e) Nitrogen 13) What coefficients must be placed in the following blanks so that all atoms are accounted for in the products C 6 H 12 O 6 C 2 H 6 O + CO 2 a) 1;2 b) 2;2 c) 1;3 d) 1;1 e) 3;1 14) How many grams of acetic acid (C 2 H 4 O 2 ) would you use to make 8L of a 0.5M aquesous solution of acetic acid?(note: The atomic masses, in Daltons, are approximately 12 for carbon, 1 for hydrogen, 16 for oxygen) a) 60.0g b) 240.0g c) 120.0g d) 8g e).5g 15) How many molecules of glycerol (C 3 H 8 O 3 ) would be present in 1mL of a 1M glycerol solution? a) 1 x 10 7 b) 14 c) 6.02 x 10 23 d) 6.02 x 10 20 e) 6.02 x 10 26 16) What is the ph of a solution with a hydroxyl ion[oh - ] concentration of 10-9? a) ph 4 b) ph 9 c) ph 5 d) ph 6 e) ph 15 3
17) Draw the electron distribution of Chlorine ( atomic number 17 and atomic mass 35.5). How many electrons does Chlorine have in its valence shell? 18) Show how NaCl bond together. Is this an ionic or a covalent bond? If it is covalent tell whether it is polar or nonpolar? 19) How do I find the ph of a solution with a hydrogen concentration of 10-3? 20) Draw the compound of methane (CH 4 ). Is this an ionic covalent bond? If it is covalent tell whether it is polar or nonpolar? 4
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