Question

Did I answer these correctly?

1. What is the total number of principal energy levels or shells in an atom with an atomic number of 30?

a. 3
b. 4
c. 5
d. 6

I choose b.

2. The electron configuration of an atom in the ground state is 2-4. The total number of occupied principal energy levels in this atom is

a. 1
b. 2
c. 3
d. 4

I choose b.

3. In an atom that has an electron configuration of 2-7, what is the total number of electrons in its principal energy level of highest energy?

a. 2
b. 5
c. 6
d. 7

I choose a.

21. What is the total number of occupied principal energy levels in an atom of 11Na?

a. 1
b. 2
c. 3
d. 4

I choose c.

Answer 1

1. What is the total number of principal energy levels or shells in an atom with an atomic number of 30?

a. 3
b. 4
c. 5
d. 6

I choose b.
<b> Correct.</b>

2. The electron configuration of an atom in the ground state is 2-4. The total number of occupied principal energy levels in this atom is

a. 1
b. 2
c. 3
d. 4

I choose b.
<b>I don't know what 2-4 or 2-7 means. If it means 2 electrons in n = 1 and 4 in n = 2, then b is correct.</b>

3. In an atom that has an electron configuration of 2-7, what is the total number of electrons in its principal energy level of highest energy?

a. 2
b. 5
c. 6
d. 7

I choose a.
<b>a is correct if that means 2 electrons in n = 1 and 7 in n = 2.
</b>


21. What is the total number of occupied principal energy levels in an atom of 11Na?

a. 1
b. 2
c. 3
d. 4

I choose c.
<B> Correct</b>

Answer 2

thanks

Answer 3

3 is incorrect. It would be d or 7 because that’s the highest energy principal energy level(the farthest from the nucleus). 7 is the number of electrons in the second principal energy level and the second principal energy level has a higher energy level ( the first principal energy level has the lowest)