Bio 011

The name of the element with 9 electrons, 8 protons, and 10 neutrons is

• fluorine

• oxygen

• nitrogen

• lithium

• neon

Fluorine has 9 electrons and can form a maximum of_________ bonds with other elements.

• 1

• 3

• 4

• 8

• 2

Which of the following is likely to be a polar bond?

• Cl-Cl

• P-H

• C-O

• C-H

When electrons are shared in a bond, this is a(n)

• DNA bond

• covalent bond

• ionic bond

• cation bond

• hydrogen bond

Which of the following sets are LEAST likely to be attracted to each other?

• two nonpolar molecules

• two polar molecules

• a positive ion and a negative ion

• water and an ionic compound (e.g. table salt)

Which of the following is NOT true about hydrogen bonding?

• They are very strong true bonds that involve two or more metals

• They are important for maintaining the structure of DNA

• They involve hydrogen interacting with N, F, O, and Cl

• They are important for interactions between different water molecules

Why does ice float in liquid water?

• Liquid water has more kinetic energy and holds up the ice.

• Hydrogen bonds are more stable at colder temperatures and water forms a crystalline matrix which is less dense than liquid water.

• The air bubbles in ice allow it to float.

• Nonpolar covalent bonds in ice molecules keep the atoms further apart than in liquid water.

Which of the following solutions has the highest concentrations of hydrogen ions [H+]?

• seawater at pH 8

• stomach acid at pH 2

• orange juice at pH 4

• oven cleaner at pH 14

The versatility of carbon that allows it to serve as the backbone for a variety of different molecules is due to 

• the vast number of hydrogen bonds it can produce

• the ability of carbon atoms to form four covalent bonds.

• the fact that carbon usually forms ionic bonds with many different atoms.

• the abundance of carbon in the atmosphere.

Polymers are large macromolecules formed by dehydration reactions, in which individual monomers are attached to a growing polymer. 

• True

• False