Chemistry Lab 3 Essay

Submitted By trippnasty
Words: 675
Pages: 3

PRE LAB
1. Which type of compound usually has higher melting points: ionic compounds or covalent compounds? What is the reason for this difference in melting points? (3 points)
Ionic compounds tend to have higher melting and boiling points than covalent compounds. This is because ionic compounds form ionic bonds, which are much stronger than covalent bonds, and thus are harder to break apart, by means of melting.
1 Do ionic compounds conduct electricity as: (3 points)
1. Solids? No, they do not.
2. Liquids? Yes, they do.
3. Aqueous solutions (when the ionic compounds are dissolved in water)? Yes, they can.
1 Do covalent compounds conduct electricity as: (3 points)
1. Solids? No, they do not.
2. Liquids? No, they do not.
3. Aqueous solutions (when the covalent compounds are dissolved in water)? No, they do not.
LAB
Part I: Lab
Insert completed data tables for each part of the lab. Be sure that the data tables are organized and include units when necessary.
1. Melting Point (4 points)
I don’t know how to make a data table, and I cannot copy and paste it from the lab, so I will do my best to record my results here in an orderly fashion.
Substance A: Did not melt, so its melting point must be over 600 degrees Celsius.
Substance B: Melted at around 190 degrees Celsius.
Substance C: Did not melt, but changed color. Melting point must be over 600 degrees Celsius.
Substance D: Melted at around 105 degrees Celsius.
2. Conductivity (4 points)
Substance A: Did not conduct as a solid, but did conduct as a liquid and as a aqueous solution.
Substance B: Did not conduct as a solid, liquid, or aqueous solution.
Substance C: Did not conduct as a solid, but did conduct as a liquid and as an aqueous solution.
Substance D: Did not conduct as all, no matter what state of matter it was in.
Part II: Conclusion
Answer the following questions in your own words, using complete sentences.
1. Based on your observations in the lab, categorize each unidentified compound as ionic or covalent. Explain in one or two sentences why you categorized the compounds the way that you did. (5 points)
I believe that substance A was ionic, because its melting point was so high that it didn’t melt in the experiment, and conducted electricity when in a liquid form and in an aqueous form. The same was found with substance C, and so I believe that substances A and C were ionic. Substances B and D, however, are covalent because they not only melted at a relatively low temperature, but they did not conduct electricity at all.
2. Explain, in your own words, the differences between ionic and covalent bonding that account for the differences in their melting points. (4 points)
In covalent bonding,…