Chapter 2

Question 1

Atom Structure

Answer 1

Protons & neutrons are packed together in the nucleus. Electrons orbit in a cloud around the nucleus.

Question 2

Atomic # and Mass

Answer 2

Atomic #: The number of protons in an element. Written as a subscript to the left of the symbol for the element. Ex: 2He
Mass: the sum of protons plus neutrons.

Question 3

Isotope

Answer 3

Atoms that have more neutrons than other atoms.

Question 4

Covalent Bonding

Answer 4

Covalent bonds form when pairs of electrons are shared.

Question 5

Polar Molecules

Answer 5

A molecule with a net dipole as a result of the opposing charges (i.e. having partial positive and negative charges) from polar bodns arranged asymmetrically.

Question 6

Cohesion (Water)

Answer 6

Water molecues stay close t each other as their link by multiple hydrogen bonds, allowing water to work AGAINST gravity.

Question 7

Molarity

Answer 7

The number of moles of solute per liter of solution.

Question 8

pH

Answer 8

The concentration of hydrogen ions in a solution. (from basic to acidic)

Question 9

Hydrophobic

Answer 9

Lacking an affinity for water; insoluble in water.

Question 10

Hydrophilic

Answer 10

Having an affinity for water.

Question 11

Ionic Bonding

Answer 11

The attraction between two oppositely charged ions ex: Na+ and Cl-

Question 12

Hydrogen Bonding

Answer 12

An attraction between a hydrogen atom carrying a partial positive charge and an electronegative atom.

-Van der Waals interactions: these occur between transiently positive and negative regions of molecules.