Question

ssess it! section.

output station
do at least two
input stations
before this.

output:
assess
it!
2 of 4

1. which element has 2

valence electrons and is
in period 4?

a. sodium
b. carbon
c. beryllium
d. calcium

Explanation:

Step1: Analyze valence electrons and period

Valence electrons: Elements in group 2 have 2 valence electrons. Period 4 means the element is in the 4th row of the periodic table.

Step2: Evaluate each option

• A. Sodium (Na): Group 1, 1 valence electron, period 3. Eliminate.
• B. Carbon (C): Group 14, 4 valence electrons, period 2. Eliminate.
• C. Beryllium (Be): Group 2, 2 valence electrons, period 2. Eliminate.
• D. Calcium (Ca): Group 2, 2 valence electrons, period 4. Correct.

Answer:

D. Calcium