Question

the image below shows the bohr model and electron configuration for an atom. based on the information in the image, where on the periodic table is the element located?
1s²2s²2p⁶3s²3p⁶4s²

Explanation:

Step1: Determine the atomic number

The atomic number (number of protons, \( P \)) is 20, as shown in the nucleus (\( 20\ P \)).

Step2: Analyze electron configuration for period

The electron configuration is \( 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 \). The highest principal quantum number (\( n \)) is 4, so the element is in period 4.

Step3: Analyze electron configuration for group

For the outermost electrons, the configuration of the valence shell is \( 4s^2 \). Elements with \( ns^2 \) (where \( n \) is the principal quantum number) and no \( d \) electrons in the outermost shell (or in this case, the valence electrons are in \( s \)-orbital) belong to group 2 (alkaline earth metals), as the number of valence electrons (2) determines the group (for main - group elements, group number = number of valence electrons for \( s \) - block elements with \( ns^x \), \( x = 1,2 \)).

Answer:

The element has an atomic number of 20 (calcium, \( Ca \)). It is located in period 4, group 2 of the periodic table.