5 Written Questions

1. a solution in which water is a solvent
2. a measure of the relative acidity of a solution, ranging in value from 0 (most acidic) to 14 (most basic); pH stands for potential hydrogen and refers to the concentration of hydrogen ions (H+)
3. a variant form of an atom, isotopes of an element have the same number of protons and electrons but different numbers of neutrons
4. an electrically charged neutral particle (a particle having no electrical charge), found in the nucleus of an atom
5. a group of two or more atoms held together by covalent bonds

5 Matching Questions

1. chemical reactions
2. electron
3. compound
4. mass
5. covalent bond

1. a a measure of the amount of material in an object
2. b an attraction between atoms that share one or more pairs of outer-shell electrons; symbolized by a single line between the atoms
3. c a process leading to chemical changes in matter, involving the making and/or breaking of chemical bonds
4. d a substance containing two or more elements in a fixed ratio; for example, tale salt (NaCl) consists of one atom of the element sodium (Na) for every atom of chlorine (Cl)
5. e a subatonic particle with a single unit of negative electrical charge; one or more electrons move around the nucleus of an atom

5 Multiple Choice Questions

1. the smallest unit of matter that retains the properties of and element
   1. heat
   2. atom
   3. base
   4. acid
2. a type of weak chemical bond formed when the partially positive hydrogen atom participating in a polar covalent bond in one molecule is attracted to the partially negative atom participating in a polar covalent bond in another molecule (or in another part of the same macromolecule)
   1. ionic bond
   2. chemical bond
   3. covalent bond
   4. hydrogen bonds
3. the property of a liquid whereby the surface becomes cooler during evaporation, owing to a loss of highly kinetic molecules to the gaseous state
   1. covalent bond
   2. atomic number
   3. ionic bond
   4. evaporative cooling
4. an attraction between two ions with opposite electrical charges; the electrical attraction of the opposite charges holds the ions together
   1. neutron
   2. chemical bond
   3. compound
   4. ionic bond
5. anything that occupies space and has mass
   1. matter
   2. base
   3. atom
   4. mass

5 True/False Questions

1. base → a substance that decreases the hydrogen ion (H+) concentration in a solution

   True        False

2. mass number → the number of protons in each atom of a particular element

   True        False

3. polar molecule → a molecule containing polar and covalent bonds (having opposite charges on opposite ends)

   True        False

4. acid → a substance that increases the hydrogen ion concentration in a solution

   True        False

5. atomic number → the number of protons in each atom of a particular element

   True        False