Question

physical properties of materials
the peak of mount everest is 8,848 meters above sea - level, or about 5.5 miles. there is less oxygen in the air, and the temperature is always below freezing. mountain climbers depend on reliable equipment to survive in these conditions. choosing which materials to use when designing the equipment requires a great deal of thought. once you have viewed the investigative phenomenon video and completed the claim - evidence - reasoning exercise, answer these reflection questions.
1 ccc structure and function ice and water are made out of the same molecule, but they have very different properties. list two physical properties of both ice and water and describe how their structures result in those properties.
2 sep plan your investigation ice axes and carabiners are important tools used by mountaineers summiting snowy peaks. these objects need to be strong and reliable in cold temperatures. engineers have choices of materials to use in making these tools. plan an investigation that could provide the evidence needed to decide which material is best to use.

Explanation:

1. For ice and water: Ice has a lower density than water (it floats) because its water - molecule structure forms a hexagonal lattice with more space between molecules. Water is a liquid at room temperature with a relatively high surface tension due to hydrogen - bonding between its molecules.
2. To plan an investigation for ice axes and carabiners materials: First, identify candidate materials like steel alloys, titanium alloys, etc. Then, test their mechanical properties (tensile strength, hardness) at cold temperatures. Also, consider corrosion resistance in cold and wet (snowy) environments. Conduct fatigue - testing under simulated climbing conditions.

Answer:

1. Ice: Lower density (floats) due to hexagonal lattice structure; hard and brittle. Water: Liquid at room - temp, high surface tension due to hydrogen - bonding.
2. Identify candidate materials (e.g., steel and titanium alloys). Test mechanical properties (tensile strength, hardness) at cold temps. Consider corrosion resistance. Conduct fatigue - testing under simulated climbing conditions.