3
QuizMultiple Choice
Oxidation-Reduction — Unit test
Question 3 • 2026-2027_MDCPS_2003345_Chemistry_1_B-CR
The atomic symbol represents potassium-40 (K-40), a radioactive isotope that has 19 protons and 21 neutrons. Which atomic symbol could represent an isotope that results from the decay of K-40?
Answer
A
Superscript 40 subscript 18 upper A r.
B
Superscript 40 subscript 18 upper K
C
Superscript 42 subscript 20 upper C a
D
Superscript 42 subscript 20 upper K.