\begin{tabular}{|c|c|c|c|c|}
\hline \begin{tabular}{c}
Number of \\
Protons
\end{tabular} & \begin{tabular}{c}
Number of \\
Neutrons
\end{tabular} & \begin{tabular}{c}
Atomic \\
Number
\end{tabular} & \begin{tabular}{c}
Mass \\
Number
\end{tabular} & \begin{tabular}{c}
Element \\
(symbol)
\end{tabular} \\
\hline 20 & 20 & A & B & C \\
\hline 9 & D & E & 19 & F \\
\hline
\end{tabular}

Using the periodic table, complete the table to describe each atom. Type in your answers.

A: [tex]$\square$[/tex]

B: [tex]$\square$[/tex]

C: [tex]$\square$[/tex]

D: [tex]$\square$[/tex]

E: [tex]$\square$[/tex]



Answer :

To complete the table and describe each atom, let's determine the missing values step by step:

### First Row:
- Number of Protons: 20
- Number of Neutrons: 20
- Atomic Number (A): The atomic number is the number of protons, which is 20.
- Mass Number (B): The mass number is the sum of the number of protons and neutrons. So, [tex]\( B = 20 (protons) + 20 (neutrons) = 40 \)[/tex].
- Element (C): The element with the atomic number 20 is Calcium, with the symbol "Ca".

### Second Row:
- Number of Protons: 9
- Number of Neutrons (D): The number of neutrons can be found by subtracting the number of protons from the mass number. [tex]\( D = 19 (mass number) - 9 (protons) = 10 \)[/tex].
- Atomic Number (E): The atomic number is the number of protons, which is 9.
- Element (F): The element with the atomic number 9 is Fluorine, with the symbol "F".

Thus, the table is completed as follows:

[tex]\[ \begin{tabular}{|c|c|c|c|c|} \hline \begin{tabular}{c} Number of \\ Protons \end{tabular} & \begin{tabular}{c} Number of \\ Neutrons \end{tabular} & \begin{tabular}{c} Atomic \\ Number \end{tabular} & \begin{tabular}{c} Mass \\ Number \end{tabular} & \begin{tabular}{c} Element \\ (symbol) \end{tabular} \\ \hline 20 & 20 & 20 & 40 & Ca \\ \hline 9 & 10 & 9 & 19 & F \\ \hline \end{tabular} \][/tex]

Answers:
A = 20
B = 40
C = Ca
D = 10
E = 9
F = F