Question

1. find the following elements on your periodic table. record what energy level their electrons would occupy? (careful, remember d = 1 less, f = 2 less)

a. aluminum is in the n=
b. silver is in the n=
c. cerium is in the n=
d. potassium is in the n=
energy level
energy level
energy level
energy level

1. how many electrons can be held in one atomic orbital?

a. 10
b. 6
c. 2
d. 8

1. how many electrons are held in n = 4?

a. 2
b. 8
c. 18
d. 32
show me how you got that number...

1. which of the following sublevels does not exist?

a. 4f
b. 1p
c. 3s
d. 5d
what energy level does each sublevel start on?
s starts on n=
p starts on n=
d starts on n=
f starts on n=

1. write an electron configuration for the following elements:

a.) sodium
symbol:
total # of electrons: (hint: in a neutral atom electrons = protons)
electron configuration:
b.) phosphorus
symbol:
total # of electrons: (hint: in a neutral atom electrons = protons)
electron configuration:

Explanation:

Step1: Recall electron - related rules

The number of electrons in an atomic orbital is 2 according to Pauli's exclusion principle. For the number of electrons in an energy level \(n\), the formula is \(2n^{2}\). Sub - levels \(s\), \(p\), \(d\), \(f\) start at \(n = 1\), \(n=2\), \(n = 3\), \(n=4\) respectively. Electron configurations are written based on the Aufbau principle, Pauli's exclusion principle and Hund's rule.

Step2: Answer question 6

• Aluminum (\(Al\)) has an atomic number of 13. Its outer - most electrons are in the \(n = 3\) energy level.
• Silver (\(Ag\)) has an atomic number of 47. Its outer - most electrons are in the \(n = 5\) energy level.
• Cerium (\(Ce\)) has an atomic number of 58. Its outer - most electrons are in the \(n = 6\) energy level.
• Potassium (\(K\)) has an atomic number of 19. Its outer - most electrons are in the \(n = 4\) energy level.

Step3: Answer question 7

One atomic orbital can hold 2 electrons. So the answer is c. 2.

Step4: Answer question 8

Using the formula \(2n^{2}\), when \(n = 4\), \(2\times4^{2}=2\times16 = 32\). So the number of electrons in \(n = 4\) is 32. The answer is d. 32.

Step5: Answer question 9

The \(s\) sub - level starts at \(n = 1\), the \(p\) sub - level starts at \(n = 2\), the \(d\) sub - level starts at \(n = 3\) and the \(f\) sub - level starts at \(n = 4\). The \(1p\) sub - level does not exist because the \(p\) sub - level starts at \(n=2\). The answer is b. 1p.

Step6: Answer question 10A

• Sodium has the symbol \(Na\).
• The atomic number of sodium is 11, so the total number of electrons in a neutral sodium atom is 11.
• The electron configuration is \(1s^{2}2s^{2}2p^{6}3s^{1}\).

Step7: Answer question 10B

• Phosphorus has the symbol \(P\).
• The atomic number of phosphorus is 15, so the total number of electrons in a neutral phosphorus atom is 15.
• The electron configuration is \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{3}\).

Answer:

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

1. c. 2
2. d. 32
3. b. 1p

10A. Symbol: \(Na\); Total # of Electrons: 11; Electron Configuration: \(1s^{2}2s^{2}2p^{6}3s^{1}\)
10B. Symbol: \(P\); Total # of Electrons: 15; Electron Configuration: \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{3}\)