halliegeorge02
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A student explained to the class that helium has 8 valence electrons because it is in group 18. Is the student correct?
- The student is incorrect because helium has 2 valence electrons and it's in group 18 because the first energy level is full. 
- The student is correct because all elements in group 8 have a full outer energy shell. 
-The student is correct because all elements in group 18 have 8 valence electrons. 
-The student is incorrect because all noble gases have 2 valence electrons. 

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MissPhiladelphia
The student is incorrect because helium has 2 valence electrons and it's in group 18 because the first energy level is full. Although helium is placed in Group 18 which generally has 8 valence electrons, it does not have 8 valence electrons as the student suggested. It was grouped together with the noble gases because it exhibits similar properties with them. 

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