Question

current attempt in progress
identify the element, with name and chemical symbol, that has a mass number of 23 and an atomic number of 11:
selenium, se.
sodium, na.
magnesium, mg.
vanadium, v.
attempts: 0 of 3 used submit

Explanation:

The atomic number determines the identity of an element. In the periodic table, the element with atomic number 11 is sodium, and its chemical symbol is Na.

Answer:

B. sodium, Na