Question

in this performance task you will answer two questions.
the electron configurations of two unknown atoms are shown.

1. based on the electron configuration of each atom, what is the number of valence electrons for each atom?

a. atom x = 1; atom y = 1
b. atom x = 1; atom y = 7
c. atom x = 10; atom y = 10
d. atom x = 11; atom y = 17

1. based on the electron configuration of atom y, to which group in the periodic table does it belong?

a. 13
b. 9
c. 17
d. 16

Explanation:

Step1: Count valence electrons for Atom X

Valence electrons are in the outermost shell. For Atom X, the outermost shell has 1 electron.

Step2: Count valence electrons for Atom Y

For Atom Y, the outermost shell has 7 electrons.

Step3: Determine group for Atom Y

In the periodic table, elements with 7 valence electrons are in group 17.

Answer:

1. B. Atom X = 1; Atom Y = 7
2. C. 17