Crystalline and Non Crystalline, Miller Indices

Which type of solid has mobile electrons in the crystal (sea of electrons)?

• Ionic Crystal
• Covalent Molecular Crystal
• Metallic Crystal
• Covalent Network Crystal

Which type of solid typically has the lowest melting point of the four types of crystals?

• Ionic Crystal
• Covalent Molecular Crystal
• Metallic Crystal
• Covalent Network Crystal

Which is an example of an ionic crystal?

• Quartz
• NaCl
• Ammonia
• Iron

Which is an example of an metallic crystal?

• Quartz
• NaCl
• Ammonia
• Iron

Which has a less clearly defined melting point?

• Amorphous Solid
• Crystalline Solid

When intermolecular forces are weak, there is a ______ boiling point and it _______ conduct electricity. 

• does not; low 
• low; does not 
• high; does 
• high; low

Melting points of pure solids are

• not defined

• high

• sharp

• low

Which one of the following diagrams best represents a smectic A liquid crystal phase?

• A

• B

• C

• D

• E

grain boundary is

• an area where some atomic mismatch within the region

  where two grains meet

• when the periodic and repeated arrangement of atoms is perfect or extends throughout the entirety of the specimen without interruption

• number of atoms centered on a plane

• crystals having hexagonal symmetry

Which of the following is a way that crystals can form in nature?

• When liquids cool and start to harden.

• When magma cools.

• When water evaporates from a mixture.

• All of the above.