Question

21. Which of the following fourth-row elements could be in the below ion? a. Geb ) As Se d) Kre ) none of these 2- 22. Consider a molecule with the below connections. When a valid electron dot structure is written, how many double bonds and how many unshared electrons will the molecule contain? 00 -0-0-0-0-H Double bonds: Unshared electrons: 23. The plastic explosive C4 contains the molecule cyclotrimethylenetrinitreamine (commonly called RDX for Royal Demolition explosive). The molecule is shown below. a) Complete the Lewis structure by adding unshared electrons. b) How many resonance structures exist for this molecule? c) Using what you know, determine which bonds are the weakest and which are the strongest. Weakest bond Strongest bond

Answer 1

lo X Number of electrons on Central atom'x' forms Oxygen atom. And central atom ex' central atom. four bonds with three have one lone pair of electron. Thus total number of valence elections: ( Number of elections involved) + (lone pair of electron). (in forming bond with '0') = 6. Total number of electrons = 4+2 OR Total number of electron in X0₂² - will be. 6 + 3x6 +2 = 26. Number of valence elections on x = 6. Therefore x must be se. Answee (6) Se. Electronic configuration : 45²4p4.

• Double bonds = 2. :: :: Unshared electrons = 16. H-0-c-c-6-H outer electronic configuration of 0 = 25°2P". Oxygen forms two bonds and have two lone pairs, Outer configuration of 'C' = 25² 2P². "C' forms four bonds in neutral condition. • H~ Is' forms 1 bond