Chemistry 201

Chemistry 122 Winter 2000 Oregon State University

Exam 1 January 20, 2000 Dr. Richard Nafshun

DO NOT OPEN THIS EXAM UNTIL INSTRUCTED.

CALCULATORS ARE NOT TO BE SHARED.

Instructions: You should have with you several number two pencils, an eraser, your 3" x 5" notecard, and your University ID Card. You may use a TI-25X Solar calculator if you wish. If you have notes with you, place them in a sealed backpack and place the backpack OUT OF SIGHT. Or place the notes directly on the table at the front of the room.

Fill in the front page of the Scantron answer sheet with your last name, first name, middle initial, and student identification number. Leave the class section number and the test form number blank.

This exam consists of 14 multiple-choice questions and 4 open-ended questions. Each multiple-choice question has five points associated with it. Select the best answer by filling in the corresponding circle on the rear page of the answer sheet. If you have any questions before the exam, please ask. If you have any questions during the exam, please raise your hand to attract the attention of a proctor. The proctor will come to you. Open and start this exam when instructed. Present your ID card when submitting the exam. Place your open-ended portion of this exam in the appropriate stack. Place your 3" x 5" notecard in the appropriate stack. You may keep the multi-choice portion of this exam, so please mark the answers you selected on it.

1. There are ___ unpaired electrons in a ground-state phosphorus atom.

(a) 0.

(b) 1.

(d) 3.

(e) 4.

2. There are ___ unpaired electrons in a ground-state oxide ion (O^2-).

(a) 0.

(b) 1.

(d) 3.

(e) 4.

3. The ground-state electron configuration of a nitrogen atom is:

(a) 1s²2s²3s²3p¹.

(b) 1s²2s²3s¹.

(d) 1s²2s²2p⁶.

(e) 1s²2s²2p³.

4. The ground-state electron configuration of an aluminum ion (Al³⁺) is:

(a) 1s²2s²3s²3p¹.

(b) 1s²2s²3s¹.

(d) 1s²2s²2p⁶.

(e) 1s²2s²2p³.

5. Consider C, N, O, and F. Arranged in decreasing atomic size, these are:

(a) C > N > O > F.

(b) F > O > N > C.

(d) N > O > C > F.

(e) C > F > O > N.

6. Consider C, Si, Ge, and Sn. Arranged in decreasing atomic size, these are:

(a) C > Si > Ge > Sn.

(b) Sn > Ge > Si > C.

(d) Si > Ge > C > Sn.

(e) Si > C > Ge > Sn.

7. A ground-state nitrogen atom has:

(a) 1 valence electron.

(b) 2 valence electrons.

(d) 5 valence electrons.

(e) 7 valence electrons.

8. A ground-state nitrogen atom has:

(a) 1 valence electron.

(b) 2 valence electrons.

(d) 5 valence electrons.

(e) 7 valence electrons.

9. A ground-state nitrogen atom is:

(a) diamagnetic.

(b) paramegnetic.

(d) Lewis magnetic.

(e) oregonianmagnetic.

10. A ground-state oxide ion is:

(a) diamagnetic.

(b) paramegnetic.

(d) Lewis magnetic.

(e) oregonianmagnetic.

11. There is/are ___ lone pair(s) of electrons on the nitrogen atom in ammonia (NH₃).

(a) 0.

(b) 1.

(d) 3.

(e) 4.

12. There is/are ___ lone pair(s) of electrons on the oxygen atom in propanol (CH₃CH₂CH₂OH).

(a) 0.

(b) 1.

(d) 3.

(e) 4.

13. Cl₂ has been isolated and characterized. The Lewis Symbol for Cl₂ indicates the

chlorine-chlorine bond is a:

(a) single bond.

(b) double bond.

(d) quadruple bond.

14. P₂ has been isolated and characterized. The Lewis Symbol for P₂ indicates the

phosphorus-phosphorus bond is a:

(a) single bond.

(b) double bond.

(d) quadruple bond.

YOU MUST SHOW ALL WORK ON NUMERICAL PROBLEMS TO RECEIVE CREDIT

1. [8 Points] Sketch the ground-state orbital energy diagram for a chlorine atom. Clearly show

every electron. Give the electron configuration for the chlorine atom.

2. [8 Points] Sketch the ground-state orbital energy diagram for a sulfide ion (S^2-). Clearly

show every electron. Give the electron configuration for the sulfide ion.

3. [2 Points] Give the Lewis Symbol for P. Show all electrons.

4. [6 Points] Give the Lewis Symbol for PH₃. Show all electrons.

5. [6 Points] Give the Lewis Symbol for CH₃COOH. Show all electrons.