Biology Chapter 2 Test

What type of bond would you expect potassium (39/19K) to form? a) ionic; it would donate one electron and carry a positive charge b) ionic; it would donate one electron and carry a negative charge c) covalent; it would share one electron and make one covalent bond d) covalent; it would share two electrons and form two bonds e) none; potassium is an inert element

a) ionic; it would donate one electron and carry a positive charge

What type of bond would you expect potassium (39/19K) to form? a. Ionic; it would donate one electron and carry a positive charge b. Ionic; it would donate one electron and carry a negative charge c. Covalent; it would share one electron and make one covalent bond d. Covalent; it would share two electrons and form two bonds e. None; potassium is an inert element

a. Ionic: it would donate one electron and carry a positive charge

In a reaction in chemical equilibrium, a. the forward and reverse reactions are occurring at the same rate b. the reactants and products are in equal concentrations c. the forward reaction has gone further than the reverse reaction. d. there are equal numbers of atoms on both sides of the equation e. a, b, and d are correct

a. the forward and reverse reactions are occurring at the same rate

A triple covalent bond would a) be very polar b) involve the bonding of 3 atoms c) involve the bonding of 6 atoms d) produce a triangularly shaped molecule e) involve the sharing of 6 electrons

b) involve the bonding of 3 atoms

A covalent bond between 2 atoms is likely to be polar if a) 1 of the atoms is much more electronegative than the other b) the 2 atoms are equally electronegative c) the 2 atoms are of the same element d) the bond is part of a tetrahedrally shaped molecule e) one atom is an anion.

b) the 2 atoms are equally electronegative

A sodium ion (Na+) contains 10 electrons, 11 protons, and 12 neutrons. What is the atomic number of sodium? a) 10 b) 11 c) 12 d) 23 e) 33

b. 11

How many covalent bonds in a sulfur atom most likely to form?

b. 2

How many electrons does phosphorus have in its valence shell?

b. 5

What types of bonds are identified in the following illustration of a water molecule interacting with an ammonia molecule? a. Bonds 1 are polar covalent bonds, bond 2 is an ionic bonds and bonds 3 are nonpolar covalent bond b. Bonds 1 and 3 are polar covalent bonds, and bond 2 is a hydrogen bond. c. Bonds 1 and 3 are polar covalent bonds, and bond 2 is an ionic bond. d. Bonds 1 and 3 are nonpolar covalent bonds, and bond 2 is a hydrogen bond. e. Bonds 1 and 3 are polar covalent bonds, and bond 2 is a nonpolar covalent bond.

b. Bonds 1 and 3 are polar covalent bonds, and bond 2 is a hydrogen bond.

Which of the following is a molecule capable of forming hydrogen bonds? a. CH4 b. H2O c. NaCl d. H2 e. a, b, and d can form hydrogen bonds

b. H2O

Each element has its own characteristic atom in which a. the atomic mass is constant b. the atomic number is constant c. the mass number is constant d. two of the above are correct e. all of the above are correct

b. the atomic number is constant

Oxygen has eight electrons. You would expect the arrangement of these electrons to be a. eight in the second electron shell, creating an inert element b. two in the first electron shell and six in the second, creating a valence of six c. two in the 1s orbital and two each in the three 2p orbitals, creating a valence of two d. two in the 1s orbital, one each in the 2s and three 2p orbitals, and two in the 3s orbital, creating a valence of two e. two in the 1s orbital, two in both the 2s and 2px orbitals, and one each in the 2py and 2pz orbitals, creating a valence of two

b. two in the first electron shell and six in the second, creating a valence of six

How many of these elements are found next to each other (side by side) on the periodic table? [elements: C O H N S P] a) 1 group of 2 b) 2 groups of 2 c) 1 group of 2 and 1 group of 3 d) 1 group of 3 e) all of them

c) 1 group of 2 and 1 group of 3

The ability of morphine to mimic the effects of the body's endorphins is due to a) a chemical equilibrium developing between morphine and endorphins b) the one-way conversion of morphine into endorphin c) molecular shape similarities d) the similarities between morphine and heroin e) hydrogen bonding and other weak bonds forming between morphine and endorphins

c) molecular shape similarities

Chlorine has an atomic number of 17 and a mass number of 35. How many electrons would a chloride ion have? a) 16 b) 17 c) 18 d) 33 e) 34

c. 18

What is the atomic weight of phosphorus?

c. 31

A radioactive isotope of carbon has the mass number 14. How many neutrons does this isotope have?

c. 8

What is the molecular shape of methane (CH4)? a. planar or flat, with the H arranged around the C b. pentagonal, or a flat five-sided arrangement c. tetrahedral, due to the hybridization of the s and three p orbits of the C d. circular, with the four H attached in a ring around the C e. linear, since all the bonds are nonpolar covalent

c. tetrahedral, due to the hybridization of the s and three p orbits of the C

Taking into account the valences of carbon and oxygen, how many hydrogen must be added to complete the structural diagram of this molecule? O..................... \\.................. .....C-C-C-C=C-C-C /................... O...

d. 12

What is the difference between a molecule and a compound? a. There is no difference; the terms are interchangeable b. Molecules contain atoms of a single element, whereas compounds contain two or more elements. c. A molecule consists of two or more covalently bonded atoms; a compound contains two or more atoms held by ionic bonds d. A compound consists of two or more elements in a fixed ratio; a molecule has two or more covalently bonded atoms of the same or different elements. e. Compounds always consist of molecules, but molecules are not always compounds.

d. A compound consists of two or more elements in a fixed ratio; a molecule has two or more covalently bonded atoms of the same or different elements.

Radioactive isotopes can be used in studies of metabolic pathways because a. their half life allows a researcher to time an experiment b. they are more reactive c. the cell does not recognize the extra protons in the nucleus, so isotopes are readily used in metabolism. d. their location or quantity can be experimentally determined because of their radioactivity e. their extra neutrons produce different colors that can be traced throughout the body.

d. their location or quantity can be experimentally determined because of their radioactivity

Which of the following weak bonds may form between any closely aligned molecules? a) nonpolar covalent b) polar covalent c) ionic d) hydrogen e) van der Waals interactions

e) van der Waals interactions

Which of the following atomic numbers would describe the element that is least reactive? a. 1 b. 8 c. 12 d. 16 e. 18

e. 18

A cation a) has gained an electron b) can easily form hydrogen bonds c) is more likely to form from an atom with 6 or 7 electrons in its valence shell d) has a positive charge e) Both c and d are correct

e. Both c and d are correct

Based on electron configuration, which of these elements would have chemical behavior most like that of oxygen? a) C b) H c) N d) P e) S

e. S