D! It’s a pure substance and a compound
Answer:
The mass number is defined as the total number of protons and neutrons in an atom.
Explanation:
Zinc (Zn) has less than 34 protons, 30 to be exact, and is a transition metal in Group 12. Note: it is also called a "post-transition metal."
Record observations, pose a question, create a test for an individual variable, test, come to a conclusion
