Which of the following best represents the Lewis dot structure for helium (He, atomic number 2). * X X X X X X X X X A B C D E F G H I O A O B O C O D O E O F O G O H O I 1. How many total electrons are found in potassium (K, atomic number 19)? 1 point Your answer
The Correct Answer and Explanation is:
The Lewis dot structure for helium (He) shows the element’s valence electrons, which are represented as dots around the symbol. Helium, with atomic number 2, has two valence electrons. Since it is a noble gas, it has a stable electron configuration with its 2 electrons filling its 1s orbital.
Looking at the options in the image, the correct representation of helium’s Lewis dot structure is:
- Option B: Two dots around the He symbol.
Helium’s electron configuration is 1s², meaning both valence electrons are paired in the 1s orbital. Therefore, the dots would be placed side by side to reflect this pairing.
Potassium (K) Electrons:
Potassium (K) has an atomic number of 19, meaning it has 19 total electrons. Potassium is in the 4th period of the periodic table, and its electron configuration is [Ar] 4s¹. This shows that after the argon core (18 electrons), potassium has 1 additional electron in the 4s orbital. Therefore, potassium has a total of 19 electrons.
Thus, the correct answer to how many electrons are in potassium is 19.
