شیمی 2 و 3 همه چیز در مورد شیمی 2 و 3 آخرین مطالب
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بار صوري يا بار قراردادي Even though the structures look the same, the formal charge (FC) may not be. Formal charges are charges that are assigned to a specific atom in a molecule. If computed correctly, the overall formal charge of the molecule should be the same as the oxidation charge of the molecule (the charge when you write out the empirical and molecular formula) We want to choose the resonance structure with the least formal charges that add up to zero or the charge of the overall molecule. The equation for finding Formal Charge is: فرمول محاسبه بار صوري Formal Charge = (number of valence electrons in free orbital) - (number of lone-pair electrons) - ( number bond pair electrons) The formal charge have to equal the molecule's overall charge. مثال ساختار لوويس مدل زير را بيابيد(Remember the Lewis Structure rules.) CNS -2. Resonance: All elements want an octet, نكته ي مهم and we can do that in multiple ways by moving the terminal atom's electrons around (bonds too). حالا سه ساختار ميتونيم با رعايت اكتت داشته باشيم 3. Assign Formal Charges by using: Formal Charge = (number of valence electrons in free orbital) - (number of lone-pair electrons) - ( number bond pair electrons) C = 4 valence e-, N = 5 valence e-, S = 6 valence e-, also add an extra electron for the (-1) charge. The total of valence electrons is 16. قسمت مهم 4.Find the most ideal resonance structure. (Note: It is the one with the least formal charges that adds up to zero or to the molecule's overall charge.) سوال : كدام ساختار صحيح است؟ جواب در مرحله 5 5. Now we have to look at electronegativity for the "Correct" Lewis structure. The most electronegative atom usually has the negative formal charge, while the least electronegative atom usually has the positive formal charges. اينم جدول الكترونگاتيوي نظرات شما عزیزان: پيوندها
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