Question

1. sep analyze data

complete the table with the mass number, number of protons, number of neutrons, and number of electrons for the elements shown.
element mass number p⁺ n e⁻
fluorine 10 9
argon 40 22
calcium 41 20

Explanation:

Step1: Recall element - property relationships

The atomic number ($Z$) is equal to the number of protons ($p^{+}$) and for a neutral atom, the number of electrons ($e^{-}$) is equal to the number of protons. The mass number ($A$) is the sum of the number of protons and neutrons ($n$), i.e., $A=p^{+}+n$.

Step2: For Fluorine

Fluorine has an atomic number of 9. So the number of protons $p^{+}=9$. Since the number of neutrons $n = 10$, the mass number $A=p^{+}+n=9 + 10=19$. And for a neutral atom, the number of electrons $e^{-}=9$.

Step3: For Argon

The mass number $A = 40$ and the number of neutrons $n=22$. Using $A=p^{+}+n$, we can find the number of protons $p^{+}=A - n=40 - 22 = 18$. For a neutral atom, the number of electrons $e^{-}=18$.

Step4: For Calcium

The mass number $A = 41$ and the number of electrons $e^{-}=20$. Since for a neutral atom $p^{+}=e^{-}$, the number of protons $p^{+}=20$. Using $A=p^{+}+n$, we can find the number of neutrons $n=A - p^{+}=41-20 = 21$.

Answer:

Element	Mass Number	$p^{+}$	$n$	$e^{-}$
Argon	40	18	22	18
Calcium	41	20	21	20