On-line Test Guidelines

I will accept corrections on tests and other major assignments to give you an additional opportunity to review concepts discussed in class and to receive a portion of the points you may have lost.  In order to submit corrections, the following guidelines must be followed carefully and completely. Remember, this is extra credit and deserve extra effort.

You must demonstrate that you UNDERSTAND the concept with your written explanation to earn the point back! I am VERY picky about giving points back!

1. Corrections are only accepted for multiple choice questions.
2. Corrections are extra extra credit and no work will be submitted after this deadline will not be accepted.
3. Corrections on a test should be considered work on a TEST.  In other words, this should be your own work without assistant from others.  You may NOT work with other students.  You may see me for clarification.
4. Your corrections are to include the following:
1. Explanation of why your initial response was wrong.  You may do this by possibly defining the term or concept and explaining how it is not the correct answer for the question.  You MAY NOT simply restate the answer here.
2. Your new response.
3. Explanation of why your new response is correct.  Again, you may want to define terms and/or concepts to support your reasoning.  Here, it may be appropriate to explain why the other choices are wrong. Be sure that you explain the concept identified in the question.
5. Corrections must be typed.
6. The corrections must be submitted along with the original test or assignment.
7. Do not write on the original test or assignment.
8. You will receive 1/2 of the points back for each correct response. 

 Examples:  (Note: you need to retype the questions)

1. A hydrogen bond is:

1. A sharing of a pair of electrons between a hydrogen nucleus and either an oxygen or a nitrogen nucleus.
2. A weak attractive force that involves a hydrogen atom and an oxygen or a nitrogen atom.
3. A sharing of a pair of electrons between a hydrogen and an oxygen nucleus.
4. None of these.
5. All of these.

Although hydrogen bonds do involve a hydrogen and either an oxygen or nitrogen atom, (A) response is incorrect because hydrogen bonds are not the result of the sharing of electrons.  Sharing of electrons form a far stronger bond referred to as covalent bonds.This also eliminates (e) as a choice.  (b) is the correct answer because hydrogen bonds are weak interactions between hydrogens and either a oxygen or nitrogen. See my diagram below.

1. Which statement is false about an chlorine atom (Cl)?

1. It has seven electrons in its valence shell.
2. It will lose its seven electrons in the valence shell to become stable.
3. It will gain one electron into its valence shell to become stable.
4. It will have a charge of -1 in its stable ionic form.
5. Once ionized (turns into an ion), it may interact with a potassium ion.

 

a.  My initial answer was (a).  This statement is a true statement, thus not the correct answer for the question.  On the periodic table, chlorine is found in column 17, indicating that it has 7 electrons in its valence shell. 

b.  (b)

c.  (c) cannot be correct because as stated earlier, chlorine has 7 electrons in its valence shell.  A complete shell requires 8, making (c) a true statement.  This also supports (d), since by having one excess electron (Cl has 17 protons and now 18 electrons with its valence shell filled), Cl will have a charge of -1.  (e) is also correct.  Potassium (K) is an element in column 1, indicating that it has one electron in its valence shell.  K is more stable in its ionic form with a charge of +1.  Since positive ions and negative ions interact through ionic bonds, (e) is a true statement.  (b) is the remaining choice, and is a false statement because the atom will GAIN 1 electron to fill its valence shell instead of losing 7.