Compare and contrast ionic and covalent bonds venn diagram

BONDING AND INTERACTIONS

15.1 Water and Its Properties

The bonding between water molecules differs when water is in different states, giving it different properties. Reading Strategy Compare and Contrast Organizing information in a table helps you compare and contrast several topics at one time. Compare water in the liquid state to water in the solid state. As you read, ask yourself, “How are they similar? How are they different?”

As you read Lesson 15.1, use the compare and contrast table below. EXTENSION Make a Venn diagram of the information in the compare and contrast table.

Lesson Summary Water in the Liquid State The polarity of water molecules causes its high surface temperature, low vapor pressure, and high boiling point.

The O—H bonds in a water molecule are polar because oxygen is more electronegative than hydrogen. Hydrogen bonding between water molecules occurs because a hydrogen atom is weakly bonded to an unshared electron pair of another water molecule’s oxygen atom.

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Attributes of water Water in the liquid state Water in the solid state

Physical properties

How atoms bond

Relative density

Water in the liquid state

Water in the solid state

Essential Understanding

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high surface tension
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low vapor pressure
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high boiling point
Name Class Date Water in the Solid State Hydrogen bonding gives ice unique properties.

Hydrogen bonds hold water molecules in place in the solid phase, so ice is less dense than water. Because ice is less dense than liquid water, ice floats on liquid water.

After reading Lesson 15.1, answer the following questions.

Water in the Liquid State 1. What unique substance is essential to all life on Earth? 2. Approximately what fraction of Earth’s surface is covered in water? 3. Circle the letter next to each sentence that is true concerning water molecules.

a. Each O—H covalent bond in a water molecule is nonpolar. b. In a water molecule, the less electronegative hydrogen atoms acquire a partial positive

charge and the oxygen atom acquires a partial negative charge. c. Because the water molecule has an H—O—H bond angle of 105°, the molecule as a

whole is polar. 4. The diagram below depicts a water molecule. Complete the labels showing the locations

of the hydrogen atoms, the oxygen atom, and the regions of positive and negative charge.

5. The diagram below depicts a collection of water molecules. Draw dotted lines showing where hydrogen bonding occurs.

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Name Class Date

6. Circle the letter next to each sentence that describes a result of the surface tension of water. a. In a full glass of water, the water surface seems to bulge over the rim of the glass. b. Water beads up into small, nearly spherical drops on a paper towel. c. Water forms nearly spherical drops at the end of an eyedropper. d. An insect called a water strider is able to “walk” on water.

7. Using Figure 15.4, explain why a water drop has surface tension.

8. Do liquids that have higher surface tension produce drops that are flatter or more nearly spherical than liquids with lower surface tension?

9. What is the name for an agent, such as a detergent, that has the ability to reduce surface tension?

Water in the Solid State 10. What happens to the density of most substances as they cool and solidify?

11. The diagrams below show hydrogen bonding between water molecules.

a. Which diagram depicts ice? b. Which diagram depicts liquid water? c. Why is ice less dense than liquid water? Refer to the diagrams to help you explain.

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Hydrogen bonds

(i) (ii)

Name Class Date 12. Look at Table 15.1. To four significant figures, list the density of

a. liquid water at 4°C b. liquid water at 0°C c. ice at 0°C

13. What is unusual about the data in Question 12? Will ice float on liquid water?

15.2 Homogeneous Aqueous Systems

Water forms aqueous solutions with other compounds, and

usually those compounds are ionic or polar covalent. Reading Strategy Combination Notes Combination notes help you to convey ideas in words and pictures at the same time. Write Solutions at the top of the T. In the left column, write brief phrases about solutions and the solution process. In the right column, draw pictures that help you visualize these concepts.

As you read Lesson 15.2, use the T-chart below. As you read about solutions and solvation, write notes on the left side of the T and illustrate them with molecular diagrams on the right side. EXTENSION Complete another T-chart that shows the differences in ionic concentration and movement for nonelectrolytes, weak electrolytes, and strong electrolytes.