A neutral atom has the following electronic configuration: 1s 2 2s 2 2p 6 3s 2 3p 5
-How many protons are in the atomic nucleus?
A)4
B)7
C)12
D)17
E)34

Question

A neutral atom has the following electronic configuration: 1s 2 2s 2 2p 6 3s 2 3p 5 
-How many protons are in the atomic nucleus?
A)4
B)7
C)12
D)17
E)34

Quizplus · Accepted Answer

The atomic number of an element is equal to the number of protons in its nucleus. To find the atomic number, we need to add up the number of electrons in each shell. In this case, there are 2 electrons in the first shell (1s2), 2 in the second (2s2), 6 in the third (2p6), 2 in the fourth (3s2), and 5 in the fifth (3p5). Adding these up gives us a total of 17 electrons. Since the atom is neutral, there must be an equal number of protons in the nucleus, which is also 17. Therefore, the answer is (D) 17.

A Neutral Atom Has the Following Electronic Configuration: 1s2 2s2

A Neutral Atom Has the Following Electronic Configuration: 1s² 2s²