University:
Purdue University
Course:
CHM 11200 | General Chemistry
Academic year:

2019
Views:

331

Pages:

5
Author:

Pranav Whitney

Bond Classification Part I. Physical Appearance For each of the following solids, include a physical description by observing the solid and cut/paste an appropriate picture (see back page) of the molecular structure of the solid in the space provided. Crystalline Solid C10H8 naphthalene Cu copper NH4NO3 ammonium nitrate (SiO2)x quartz NH3 ammonia Physical Description Example of Molecular Structure Crystalline Solid KCl potassium chloride I2 iodine Cx Graphite H2O water Mg Magnesium Physical Description Example of Molecular Structure Part II. Physical Properties For each of the crystalline solids, determine melting point, boiling point, and conductivity data using the CRC reference guide and conductivity meter. When reporting melting and boiling points, be sure to indicate whether values are in °C or K. When testing solids for conductivity, be sure to wear safety glasses. Finally, classify each crystalline solid as Ionic, Covalent network, Metallic, Covalent molecular (nonpolar), or Covalent molecular (polar). Crystalline Solid C10H8 naphthalene Cu copper NH4NO3 ammonium nitrate (SiO2)x quartz NH3 ammonia Melting Point Boiling Point Conductivity Classification Crystalline Solid KCl potassium chloride I2 iodine Cx Graphite H2O water Mg Magnesium Melting Point Boiling Point Conductivity Classification Part III. Data Analysis Answer the following questions as completely as possible using data and your experiences from this lab. 1. Using your melting point and boiling point data from Part II, rank the ten crystalline solids in order of increasing bond strength. (Be sure to convert all temperatures to the same units (℃ or K) before making your comparison. The formula for converting Kelvin units to Celsius is: K = °C + 273.15) 2. Compare and contrast the four types of crystalline solids: Ionic, Covalent network, Metallic, and Covalent molecular. Use your experiences and data from this lab. 3. Explain why ionic crystals melt at much higher temperatures than typical covalent molecular crystals. (HINT: Looking back at question #1, what data did you use to classify bonds as weak or strong?)