CHM109 Week 4 Exercises

University of Phoenix Material

Week 4 Exercises

Preparewritten answers to the following exercises:

1. Imagine that you are an environmental scientist. Working in collaboration with a university chemist, you were able to determine from mass spectrometry that four elements exist in your soil samples. They are Se, Sn, Pb, and Cd.

You need to determine which elements will most likely combine with oxygen to produce oxides that are present in your sample. To do so, refer to the periodic table to determine the electron configuration and ionization energy of each element. This will show the number of valence electrons for each element.

· What are the electron configurations for Se, Sn, Pb, and Cd?

· What are the valence electrons for Se, Sn, Pb, and Cd?

· Rank the elements in increasing ionization energy.

· Which element will form oxides?

2. Imagine that, as an employee of a pharmaceutical company, you are working on an H-K-ATPase. It is the enzyme that pumps acid into the stomach to help in digestion. You are trying to determine whether a compound will fit inside the pocket of this enzyme in order to inhibit the enzyme. To do so, you must know the molecular shape of the compound.

Draw the Lewis structure and determine the molecular geometry of the following compounds that may fit into the active site of this enzyme:

· CO₂

· KOH

· NO₃

· HCN

3. Imagine that you work as a chemist in a battery manufacturing plant. You are asked to try a variety of substances that can be used to generate an ion potential necessary to produce electricity. Ionic compounds produce ions that can generate an ion potential when placed in an aqueous solution.

Name the various compounds in the following table and label them as ionic or molecular:

Formula	Name	Ionic or molecular
PtO2
CF2Cl2
CO
KClO3
CoSO4
CO2
SO3
Ba(NO3)2
NH4I
NaClO4