Chapter+16+Exam+Questions

=== Our bodies are about 60% water. The chemical formula of water is H2O. Explain how the elements Hydrogen and Oxygen bond covalently with one another to form this important molecule by answering the following questions: ===

=== 17. Draw a Lewis Dot Diagram for a Hydrogen atom and an Oxygen atom in the space below, and explain why your diagrams look the way they do. (Basically – explain the dots. It may be helpful to draw another picture.) ===

=== 21. List the four major kinds of carbon-based macromolecules that are important to living things, and give an example of each. In addition to Carbon, what are the 4 other major elements that make up these organic molecules? ===

=== 23. Iron (III) and Oxygen will form an **ionic compound**. Write the **chemical formula** for this compound in the space below, and provide a **detailed explanation of how you arrived at this answer**. ===

**BONUS EXTRA CREDIT QUESTION: (Worth up to 4 extra points)**
=== 24. Carbon and Silicon are both in Group 14 on the periodic table. On Earth, all living things are based on the element Carbon, but scientists think that life on other planets could be based on the element Silicon. Explain why this is a reasonable hypothesis based on what you know about the similarities between Carbon and Silicon. ===