Feb 14 HW-solutions

# Feb 14 HW-solutions - chauhan (mmc2762) Feb 14 HW sparks...

This preview shows pages 1–3. Sign up to view the full content.

chauhan (mmc2762) – Feb 14 HW – sparks – (51150) 1 This print-out should have 14 questions. Multiple-choice questions may continue on the next column or page – fnd all choices be±ore answering. Preview sectiosn 13.3 and 13.6 be±ore next class. 001 10.0 points What total number o± valence electrons should appear in the dot ±ormula ±or the chlo- rate ion ClO - 3 ? 1. 32 2. 24 3. 26 correct 4. 28 5. 30 Explanation: Chlorine has 7 valence electrons and oxy- gen 6. The overall - 1 charge indicates that there is 1 extra electron. The total number o± valence electrons is 1 × 7 e - (±rom Cl) + 3 × 6 e - (±rom O) +1 e - (±rom - 1 charge) = 26 e - 002 10.0 points How many lone pairs o± electrons are on nitrogen in NF 3 ? 1. three 2. ten 3. two 4. ±our 5. one correct 6. twenty 7. thirteen 8. none Explanation: The Lewis structure is N b F F b b F 003 10.0 points Which o± the ±ollowing is the correct Lewis ±ormula ±or oxygen (O 2 )? 1. b b b b b b b b O b b b b b b O 2. b b b b b b O b b b b b b O correct 3. O b b b b b b b b b b O 4. b b b b b b b b b b O O 5. O b b O 6. b b b b b b O b b b b b b O 7. b b b b b b O b b b b O 8. O b b b b b b b b O Explanation: N = 8 × 2 = 16 A = 6 × 2 = 12 S = N - A = 16 - 12 = 4 There are 4 shared electrons. The remain- ing electrons are placed around the oxygen atoms such that each has an octet. The Lewis dot ±ormula ±or oxygen (O 2 ) is b b b b b b O b b b b b b O 004 10.0 points How many unshared electrons and bonding electrons exist around the central atom in ozone, O 3 ? 1. two; two 2. three; six 3. zero; eight

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
chauhan (mmc2762) – Feb 14 HW – sparks – (51150) 2 4. four; three 5. one; three 6. one; six 7. two; six correct 8. none; two 9. four; four Explanation: O b O O O O b b O 005 10.0 points Which substance contains a triple bond? 1. BF 3 2. C 2 F 2 correct 3. H 2 S 4. HOF 5. H 2 CO Explanation: The Lewis structure for C 2 F 2 is F C C F b b 006 10.0 points Draw the Lewis electron dot structure for NO - 3 . What is the total number of non-shared electrons? 1.
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 04/03/2012 for the course CHEM 56920 taught by Professor Sparks during the Spring '12 term at University of Texas at Austin.

### Page1 / 5

Feb 14 HW-solutions - chauhan (mmc2762) Feb 14 HW sparks...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online