Question

#protons =
atomic # =
#electrons = 9
#neutrons =
mass # =
f-19

Explanation:

Step1: Identify element from symbol

Fluorine (F) has atomic number 9. In a neutral atom, the number of protons equals the atomic number and the number of electrons. So, the number of protons = 9.

Step2: Determine atomic number

The atomic number of fluorine is 9.

Step3: Calculate number of neutrons

The mass - number of F - 19 is 19. The formula for mass number (A) is $A =$ number of protons ($p$)+ number of neutrons ($n$). Given $A = 19$ and $p = 9$, then $n=A - p=19 - 9 = 10$.

Step4: Recall mass number notation

The notation F - 19 indicates that the mass number is 19.

Answer:

#Protons = 9
Atomic # = 9
#electrons = 9
#neutrons = 10
Mass # = 19