Biology Chapter 2 Pre-Lecture – Flashcards

What type of bond is joining the two hydrogen atoms? a. covalent b. hydrophobic c. hydrophilic d. ionic e. hydrogen

A(n) _____ refers to two or more atoms held together by covalent bonds. a. community b. ion c. isotope d. shell e. molecule

This atom can form up to _____ single covalent bond(s). a. 0 b. 3 c. 2 d. 1 e. 4

A(n) _____ bond joins these two oxygen atoms. a. ionic b. hydrogen c. double covalent d. single covalent e. quadruple covalent

The brackets are indicating a(n) _____ bond. a. polar covalent b. hydrogen c. ionic d. hydrophobic e. single (nonpolar) covalent

What name is given to the bond between water molecules? a. hydrogen b. ionic c. single (nonpolar) covalent d. hydrophobic e. polar covalent

Atoms with the same number of protons but with different electrical charges _____. a. have different atomic numbers b. are different isotopes c. are different ions d. have different atomic masses e. have different numbers of neutrons

In salt, what is the nature of the bond between sodium and chlorine? a. ionic b. hydrogen c. hydrophobic d. polar covalent e. nonpolar covalent

What is the result of the animated process? a. a negatively charged sodium ion and a positively charged chlorine ion b. a negatively charged sodium ion and a negatively charged chlorine ion c. covalent bond formation d. a positively charged sodium ion and a positively charged chlorine ion e. a positively charged sodium ion and a negatively charged chlorine ion

An ionic bond involves _____. a. water avoidance b. the unequal sharing of an electron pair c. no atoms other than sodium and chlorine d. the sharing of a single pair of electrons e. an attraction between ions of opposite charge

What type of bond joins the carbon atom to each of the hydrogen atoms? a. polar covalent b. single (nonpolar) covalent c. double (nonpolar) covalent d. hydrogen e. ionic

What does the term electron orbital describe? a. An electron orbital describes the exact distance of an electron from the nucleus. b. An electron orbital describes a three-dimensional space where an electron can be found 90% of the time. c. An electron orbital describes the orbit of an electron around the nucleus.

What happens when two atoms form a chemical bond? a. A chemical bond forms when two atoms transfer or share protons to achieve a stable nucleus. b. Two atoms fuse together to form a chemical bond. c. A chemical bond forms when two atoms transfer or share outer electrons to complete their outer shells.

In the term trace element, the adjective trace means that a. the element is very rare on Earth. b. the element can be used as a label to trace atoms through an organism's metabolism. c. the element is required in very small amounts. d. the element passes rapidly through the organism. e. the element enhances health but is not essential for the organism's long-term survival.

Compared with 31P, the radioactive isotope 32P has a. a different atomic number. b. a different charge. c. one more neutron. d. one more proton. e. one more electron.

Which statement is true of all atoms that are anions? a. The atom has more neutrons than protons. b. The atom has more protons than electrons. c. The atom has fewer protons than does a neutral atom of the same element. d. The net charge is 1-. e. The atom has more electrons than protons.

Which of the following statements correctly describes any chemical reaction that has reached equilibrium? a. The reaction is now irreversible. b. Both forward and reverse reactions have halted. c. The rates of the forward and reverse reactions are equal. d. The concentrations of products and reactants are equal. e. No reactants remain.

The atomic number of sulfur is 16. Sulfur combines with hydrogen by covalent bonding to form a compound, hydrogen sulfide. Based on the number of valence electrons in a sulfur atom, predict the molecular formula of the compound. a. HS b. H3S2 c. H4S d. HS2 e. H2S

Which statement about weak bonds is correct? a. Weak bonds are transient and easily reversible. b. Weak chemical bonds form only between atoms of similar electronegativity. c. Weak bonds are less important to living things than strong covalent bonds.