Valence electrons: Cl – 7, O – 6, C – 4, N – 5

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Presentation transcript:

Valence electrons: Cl – 7, O – 6, C – 4, N – 5 QUESTION: A structure obeying the octet/duet rule can be drawn for a molecule consisting of 3 hydrogen atoms and which one of these atoms? A. Cl, B. O, C. C, D. N Hydrogen follows the duet rule --- always found to form only one single bond. Valence electrons: Cl – 7, O – 6, C – 4, N – 5 To get an octet, atom must be surrounded by 8 electrons. SCRIPT: 3-5-3 A structure obeying the octet or duet rule can be drawn for a molecule consisting of three hydrogen atoms and which of these atoms… Chlorine Oxygen Carbon Or nitrogen CLICK Hydrogen atoms follow the duet rule. They have only one electron and needs only one more to be isoelectronic with helium. By referring to the periodic table, we will find that Chlorine belongs to group seven A… therefore, it has seven valence electrons…. Shown here by seven dots drawn around the symbol for chlorine… Oxygen belongs to group six A… therefore, it has six valence electrons… Carbon belongs to group four A… it has four valence electrons… Nitrogen belongs to group five A… it has five valence electrons… In order to acquire an octet, these atoms need to share electrons with other atoms. In this question, we are asked which one will be able to achieve an octet by sharing electrons with three hydrogen atoms. Let’s see… Chlorine already has seven valence electrons. It needs just one more to acquire an octet. This is accomplished by bonding with only one hydrogen atom. CLICK… We can see that chlorine is now surrounded by eight electrons. Oxygen has six valence electrons. To acquire an octet, it needs to bond with two hydrogen atoms. CLICK… CLICK….CLICK Carbon has four valence electrons. To acquire an octet, it needs to bond with four hydrogen atoms. CLICK… CLICK…. CLICK… CLICK… CLICK Finally, nitrogen has five valence electrons. To acquire an octet, it needs to bond with three hydrogen atoms. CLICK… CLICK… CLICK… CLICK The correct answer is nitrogen. PAUSE 2 seconds END RECORDING

Video ID: 3-5-3 © 2008, Project VALUE (Video Assessment Library for Undergraduate Education), Department of Physical Sciences Nicholls State University Author: Glenn V. Lo Funded by Louisiana Board of Regents Contract No. LA-DL-SELECT-13-07/08