National and Regional Contests USA Contests USA Physics and Chemistry Contests National Chemistry Olympiad 2013 National Chemistry Olympiad 50 2013 USNCO Problem 50: Strongest Bond Problem Statement Which bond is strongest?< s p a n c l a s s = ′ l a t e x − b o l d ′ > ( A ) < / s p a n > C=C < s p a n c l a s s = ′ l a t e x − b o l d ′ > ( B ) < / s p a n > C=N < s p a n c l a s s = ′ l a t e x − b o l d ′ > ( C ) < / s p a n > C=O < s p a n c l a s s = ′ l a t e x − b o l d ′ > ( D ) < / s p a n > C=S { <span class='latex-bold'>(A)</span>\ \text{C=C}\qquad<span class='latex-bold'>(B)</span>\ \text{C=N}\qquad<span class='latex-bold'>(C)</span>\ \text{C=O}\qquad<span class='latex-bold'>(D)</span>}\ \text{C=S}\qquad < s p an c l a ss = ′ l a t e x − b o l d ′ > ( A ) < / s p an > C=C < s p an c l a ss = ′ l a t e x − b o l d ′ > ( B ) < / s p an > C=N < s p an c l a ss = ′ l a t e x − b o l d ′ > ( C ) < / s p an > C=O < s p an c l a ss = ′ l a t e x − b o l d ′ > ( D ) < / s p an > C=S