Question

element name | isotopic symbol | atomic number | mass number | # of protons | # of neutrons | # of electrons | average atomic mass
--- | --- | --- | --- | --- | --- | --- | ---
potassium | k-39 | 19 | 39 | 19 | 20 | 19 | 39.098
carbon | c-13 | 6 | 13 | 6 | 7 | 6 | 12.011
chlorine | cl-35 | 17 | 35 | 17 | 18 | 17 | 35.45

	11	22
			18	21

Explanation:

To solve the missing values in the table, we use the following relationships:

• Atomic Number = Number of Protons = Number of Electrons (in a neutral atom).
• Mass Number = Number of Protons + Number of Neutrons.
• Element Name is determined by Atomic Number (from the periodic table).

Row 4 (Atomic Number = 11, Mass Number = 22)

Step 1: Identify Element Name

Atomic Number = 11 corresponds to Sodium (Na).

Step 2: Number of Protons

Atomic Number = Number of Protons = $11$.

Step 3: Number of Neutrons

Mass Number = Protons + Neutrons $\implies$ Neutrons = Mass Number $-$ Protons = $22 - 11 = 11$.

Step 4: Number of Electrons

In a neutral atom, Electrons = Protons = $11$.

Step 5: Isotopic Symbol

Isotopic Symbol: $\text{Na-}22$ (since Mass Number = 22).

Row 5 (Protons = 18, Neutrons = 21)

Step 1: Atomic Number

Atomic Number = Number of Protons = $18$.

Step 2: Element Name

Atomic Number = 18 corresponds to Argon (Ar).

Step 3: Mass Number

Mass Number = Protons + Neutrons = $18 + 21 = 39$.

Step 4: Number of Electrons

In a neutral atom, Electrons = Protons = $18$.

Step 5: Isotopic Symbol

Isotopic Symbol: $\text{Ar-}39$ (since Mass Number = 39).

Filled Table (Key Rows):

Element Name	Isotopic Symbol	Atomic Number	Mass Number	# of Protons	# of Neutrons	# of Electrons	Average Atomic Mass
Carbon	C-13	6	13	6	7	6	12.011
Chlorine	Cl-35	17	35	17	18	17	35.45
Sodium	Na-22	11	22	11	11	11	(varies, but table focuses on isotope)
Argon	Ar-39	18	39	18	21	18	(varies, but table focuses on isotope)

Final Answers for Missing Rows:

• Row 4 (Atomic Number = 11, Mass Number = 22):

Element Name: Sodium, Isotopic Symbol: Na-22, # of Protons: 11, # of Neutrons: 11, # of Electrons: 11.

• Row 5 (Protons = 18, Neutrons = 21):

Element Name: Argon, Isotopic Symbol: Ar-39, Atomic Number: 18, Mass Number: 39, # of Electrons: 18.

Answer:

To solve the missing values in the table, we use the following relationships:

• Atomic Number = Number of Protons = Number of Electrons (in a neutral atom).
• Mass Number = Number of Protons + Number of Neutrons.
• Element Name is determined by Atomic Number (from the periodic table).

Row 4 (Atomic Number = 11, Mass Number = 22)

Step 1: Identify Element Name

Atomic Number = 11 corresponds to Sodium (Na).

Step 2: Number of Protons

Atomic Number = Number of Protons = $11$.

Step 3: Number of Neutrons

Mass Number = Protons + Neutrons $\implies$ Neutrons = Mass Number $-$ Protons = $22 - 11 = 11$.

Step 4: Number of Electrons

In a neutral atom, Electrons = Protons = $11$.

Step 5: Isotopic Symbol

Isotopic Symbol: $\text{Na-}22$ (since Mass Number = 22).

Row 5 (Protons = 18, Neutrons = 21)

Step 1: Atomic Number

Atomic Number = Number of Protons = $18$.

Step 2: Element Name

Atomic Number = 18 corresponds to Argon (Ar).

Step 3: Mass Number

Mass Number = Protons + Neutrons = $18 + 21 = 39$.

Step 4: Number of Electrons

In a neutral atom, Electrons = Protons = $18$.

Step 5: Isotopic Symbol

Isotopic Symbol: $\text{Ar-}39$ (since Mass Number = 39).

Filled Table (Key Rows):

Element Name	Isotopic Symbol	Atomic Number	Mass Number	# of Protons	# of Neutrons	# of Electrons	Average Atomic Mass
Carbon	C-13	6	13	6	7	6	12.011
Chlorine	Cl-35	17	35	17	18	17	35.45
Sodium	Na-22	11	22	11	11	11	(varies, but table focuses on isotope)
Argon	Ar-39	18	39	18	21	18	(varies, but table focuses on isotope)

Final Answers for Missing Rows:

• Row 4 (Atomic Number = 11, Mass Number = 22):

Element Name: Sodium, Isotopic Symbol: Na-22, # of Protons: 11, # of Neutrons: 11, # of Electrons: 11.

• Row 5 (Protons = 18, Neutrons = 21):

Element Name: Argon, Isotopic Symbol: Ar-39, Atomic Number: 18, Mass Number: 39, # of Electrons: 18.