27. Amorphous solids have crystal structures.- F?

32. Pure, crystalline solids freeze and melt at the same temperature.- F

34. Water expands as it freezes.- T

Thanks
-MC

34. Bad question. The answer depends on what you mean "as it freezes". Water has a maximum density at 4C, and it lessens density as it cools or heats. Lessen density means expand.

However, water at 12C is considerably less dense than ice, so if you are comparing those two temps, then water contracts "as it freezes". Look at the graph.
http://www.marietta.edu/~mcshaffd/aquatic/sextant/physden.gif
You teacher probably wants "true" there.

32. The melting point of anything is the same as the freezing point. Student's always think they are different but they are the same. If water freezes at 32 F it must also melt at 32 F. So water at 32 F does what? freeze or melt? It depends upon which way the heat is going. If you have it in a freezer it will freeze. If you have it on a table at room temperature, it will melt.

27. The statement "Amorphous solids have crystal structures" is false. Amorphous solids do not have a well-defined, repeating crystal structure. Instead, their atoms or molecules are arranged in a random or disordered manner. Examples of amorphous solids include glass and some plastics.

To arrive at this answer, you can recall the definition of amorphous solids, which states that they lack a regular crystalline structure. Alternatively, you can also conduct research on amorphous solids or consult a reliable source such as textbooks or scientific articles for more information.

32. The statement "Pure, crystalline solids freeze and melt at the same temperature" is false. Crystalline solids have a specific freezing point and a specific melting point, which are typically different temperatures.

To determine the correctness of this statement, you can rely on your knowledge of crystalline solids or consult a scientific resource. Crystals have a highly ordered arrangement of atoms or molecules, and their melting point is generally higher than their freezing point due to the energy required to disrupt the crystal lattice.

34. The statement "Water expands as it freezes" is true. Unlike most substances, the density of water decreases as it freezes, causing it to expand.

To confirm this fact, you can perform a simple experiment or rely on scientific knowledge on the behavior of water. The expansion of water upon freezing can be attributed to the unique structure of water molecules, which arrange themselves in a hexagonal pattern in the solid state, creating an open structure and resulting in a lower density compared to liquid water.