question 1 1 pts which element has 9 protons? beryllium potassium fluorine question 2 1 pts an atom has 19…
question 1 1 pts which element has 9 protons? beryllium potassium fluorine question 2 1 pts an atom has 19 protons and 20 neutrons. what is the mass?
Answer
Explanation:
Step1: Recall atomic number concept
The atomic number of an element is equal to the number of protons. Fluorine has an atomic number of 9, so it has 9 protons.
Step2: Recall mass - number formula
The mass number of an atom is the sum of the number of protons and neutrons. Given 19 protons and 20 neutrons, the mass number is (19 + 20=39).
Answer:
Question 1: C. fluorine Question 2: 39