Question

extension: volume and density get the gizmo ready: - press chill until the water is completely frozen. introduction: the density of a substance refers to how much matter is packed into a particular space, or volume. the denser the object, the more “tightly packed” it is. objects that are less dense tend to float in denser materials. question: how do phases of water compare in volume and density? 1. form hypothesis: answer the following questions based on your personal experience and the observations you have made of the gizmo: a. does an ice cube in water float or sink? ______ b. when water boils, bubbles of water vapor form in the water. do these bubbles tend to rise or sink? ____ c. which phase of water is densest? ____ least dense? ____ 2. observe: be sure all the water is frozen. open the tools tray at upper right, and drag an arrow to mark the top of the ice. then press heat. watch until all the ice has melted. a. does the liquid water take up as much space as the ice? ____ b. wait until all the water has boiled away. which takes up more space, the liquid water or the water vapor? ____ c. which phase of water is densest? ____ least dense? ______

Explanation:

These answers are based on scientific properties of water's phases and real-world observations:

1. A. Ice is less dense than liquid water, so it floats.
2. B. Water vapor is far less dense than liquid water, so its bubbles rise.
3. C. Liquid water has the highest density among water's common phases; water vapor (gas) is the least dense.
4. A. When ice melts, the hydrogen bonds rearrange to occupy less space, so liquid water takes up less volume than ice.
5. B. When water boils into vapor, molecules spread out drastically, so water vapor takes up far more space than liquid water.
6. C. Consistent with scientific facts, liquid water is the densest phase, and water vapor (gas) is the least dense.

Answer:

1. A. Float
2. B. Rise
3. C. Densest: Liquid water; Least dense: Water vapor
4. A. No, liquid water takes up less space
5. B. Water vapor
6. C. Densest: Liquid water; Least dense: Water vapor