1. Classify each of the following as an element, a compound, or a mixture:
   1. iron
   2. oxygen
   3. mercury oxide
   4. pancake syrup
   5. carbon dioxide
   6. a substance composed of molecules each of which contains one hydrogen atom and one chlorine atom
   7. baking soda
   8. baking powder
2. Yeast converts glucose to ethanol and carbon dioxide during anaerobic fermentation as depicted in the simple chemical equation here:  [latex]\text{glucose}\rightarrow\text{ethanol}+\text{carbon dioxide}[/latex]
   1. If 200.0 g of glucose is fully converted, what will be the total mass of ethanol and carbon dioxide produced?
   2. If the fermentation is carried out in an open container, would you expect the mass of the container and contents after fermentation to be less than, greater than, or the same as the mass of the container and contents before fermentation? Explain.
   3. If 97.7 g of carbon dioxide is produced, what mass of ethanol is produced?
3. Classify the six underlined properties in the following paragraph as chemical or physical:  Fluorine is a pale yellow gas that reacts with most substances. The free element melts at −220 °C and boils at −188 °C. Finely divided metals burn in fluorine with a bright flame. Nineteen grams of fluorine will react with 1.0 gram of hydrogen.
4. How does an element differ from a compound? How are they similar?
5. Compare and contrast ionic, covalent, and hydrogen bonds.
6. What are the subatomic particles of an atom?
7. How are polar bonds different from nonpolar bonds?
8. What is the difference between groups and periods?
9. Draw the Bohr’s model and the Lewis dot formula for the following atoms, elements, and compounds:

a. Sodium

b. Chlorine

c. Sodium Chloride

d. Oxygen

e. O₂

f. N₂

g. H₂O

10. Using the periodic table, classify each of the following elements as a metal or a nonmetal, and then further classify each as a main-group (representative) element, transition metal, or inner transition metal:

1. uranium
2. bromine
3. strontium
4. neon
5. gold
6. americium
7. rhodium
8. sulfur
9. carbon
10. potassium

11. Using the periodic table, identify the lightest member of each of the following groups:

1. noble gases
2. alkaline earth metals
3. alkali metals
4. chalcogens

1. Using the periodic table, identify the heaviest member of each of the following groups:
   1. alkali metals
   2. chalcogens
   3. noble gases
   4. alkaline earth metals

12.  Use the periodic table to give the name and symbol for each of the following elements:

1. the noble gas in the same period as germanium
2. the alkaline earth metal in the same period as selenium
3. the halogen in the same period as lithium
4. the chalcogen in the same period as cadmium

13. Give the number of protons, electrons, and neutrons in neutral atoms of each of the following isotopes:

1. [latex]{}_{5}^{10}\text{B}[/latex]
2. [latex]{}_{80}^{199}\text{Hg}[/latex]
3. [latex]{}_{29}^{63}\text{Cu}[/latex]
4. [latex]{}_{6}^{13}\text{C}[/latex]
5. [latex]{}_{34}^{77}\text{Se}[/latex]

14. Predict whether the following compounds are ionic or molecular:

1. KI, the compound used as a source of iodine in table salt
2. H₂O₂, the bleach and disinfectant hydrogen peroxide
3. CHCl₃, the anesthetic chloroform
4. Li₂CO₃, a source of lithium in antidepressants