Chapter 2

What atom has only one proton? a. hydrogen b. an isotope c. a free radical d. a radioisotope

A molecule into which a radioisotope has been incorporated can be used as a(n) ___. a. compound b. tracer c. salt d. acid

Which of the following statements is incorrect? a. Isotopes have the same atomic number and different mass numbers. b. Atoms have about the same number of electrons as protons. c. All molecules consist of atoms. d. Free radicals are dangerous because they emit energy.

In the periodic table, symbols for the elements are arranged according to ___ a. size b. charge c. mass number d. atomic number

Rank the following chemical bonds in order of increasing polarity. a. nonpolar covalent b. ionic c. polar covalent

The mutual attraction of opposite charges holds atoms together as molecules in a(n) ___ bond. a. ionic b. hydrogen c. polar covalent d. nonpolar covalent

Atoms share electrons unequally in a(n) ___ bond. a. ionic b. hydrogen c. polar covalent d. nonpolar covalent

\(\mathrm{A}(\mathrm{n}) \quad\) substance repels water. a. acidic c. hydrophobic b. basic d. polar

A salt does not release ___ in water. a. ions b. \(\mathrm{H}^{+}\)

Hydrogen ions \(\left(\mathrm{H}^{+}\right)\) are ___. a. in blood b. protons c. indicated by a pH scale d. all of the above

When dissolved in water, a(n) ___ donates \(\mathrm{H}^{+}\) a(n) ___ accepts \(\mathrm{H}^{+}\). a. acid; base b. base; acid c. buffer; solute d. base; buffer

A ___ is dissolved in a solvent. a. molecule b. solute c. salt d. radioisotope

Match the terms with their most suitable description. $$ \text { hydrophilic } \quad \quad\quad\quad\quad \text { a. protons \(>\) electrons } $$ $$ \text { atomic number } \quad \quad\quad\quad\quad \text { b. number of protons in nucleus } $$ $$ \text { hydrogen bonds } \quad \quad\quad\quad\quad \text { c. polar; dissolves easily in water } $$ $$ \text { positive charge } \quad \quad\quad\quad\quad \text { d. collectively strong } $$ $$ \text { temperature } \quad \quad\quad\quad\quad \text { e. protons \(<\) electrons } $$ $$ \text { negative charge } \quad \quad\quad\quad\quad \text { f. measure of molecular motion } $$