Question

the diagram shows part of the periodic table. which element is correctly matched with its electronic structure? element electronic structure a w 2,8,1 b x 2,4 c y 2,8,2 d z 2,8

Explanation:

Step1: Recall periodic - table position and electron - shell rules

Elements in the first period have electrons only in the first shell (maximum 2 electrons), second - period elements have electrons in the first two shells (second shell can hold up to 8 electrons), and third - period elements have electrons in the first three shells.

Step2: Analyze position of W

W is in the second period and first group. It has 3 electrons. Its electron configuration is 2,1. So option A is incorrect.

Step3: Analyze position of X

X is in the second period and fourth group. It has 6 electrons. Its electron configuration is 2,4. Option B is correct.

Step4: Analyze position of Y

Y is in the third period and second group. It has 12 electrons. Its electron configuration is 2,8,2. But Y is in the wrong position for this electron - configuration in the given partial periodic table layout (it should be in the third row and second column of the main part of the periodic table shown).

Step5: Analyze position of Z

Z is in the third period and eighth group (noble gas group). It has 18 electrons. Its electron configuration is 2,8,8. So option D is incorrect.

Answer:

B. X, 2,4