Question

1. how many electrons can each sublevel hold?

a. s-
b. p-
c. d-
d. f-

1. the s sublevel can hold ____ electrons at each energy level and the electrons have ____ spins (direction).
2. the lowest energy state of an atom is its ____________ state.
3. what is the element for the following electron configuration?

b. 1s²2s²2p⁶3s²3p⁴

1. what is the atomic number for the following electron configuration?

c. 1s²2s²2p⁶3s²3p⁶4s²

1. complete the orbital diagram for nickel (ni):

1s 2s 2p 3s 3p 4s 3d

1. complete the electron configuration for the following element:

d. magnesium

1. complete the noble gas notation for the following element:

e. selenium

Explanation:

Step1: Recall electron - holding capacity of sublevels

The s sublevel has 1 orbital and can hold 2 electrons, the p sublevel has 3 orbitals and can hold 6 electrons (2 electrons per orbital), the d sublevel has 5 orbitals and can hold 10 electrons, and the f sublevel has 7 orbitals and can hold 14 electrons.
a. 2
b. 6
c. 10
d. 14

Step2: Fill in s - sublevel electron and spin information

The s sublevel can hold 2 electrons at each energy level and the electrons have opposite spins.

1. 2; opposite

Step3: Recall atomic energy state term

The lowest energy state of an atom is its ground state.

1. ground

Step4: Determine element from electron - configuration

For the electron - configuration \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{4}\), the total number of electrons is \(2 + 2+6 + 2+4=16\). The element with 16 electrons is sulfur (S).

1. S

Step5: Calculate atomic number from electron - configuration

For the electron - configuration \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}\), the total number of electrons is \(2 + 2+6 + 2+6 + 2 = 20\). The atomic number is equal to the number of electrons in a neutral atom, so the atomic number is 20.

1. 20

Step6: Write electron - configuration of magnesium

Magnesium (Mg) has an atomic number of 12. Its electron - configuration is \(1s^{2}2s^{2}2p^{6}3s^{2}\).

1. \(1s^{2}2s^{2}2p^{6}3s^{2}\)

Step7: Write noble - gas notation for selenium

Selenium (Se) has an atomic number of 34. The nearest noble gas with a lower atomic number is argon (Ar) which has 18 electrons. So the noble - gas notation is \([Ar]3d^{10}4s^{2}4p^{4}\).

1. \([Ar]3d^{10}4s^{2}4p^{4}\)

Answer:

1. a. 2, b. 6, c. 10, d. 14
2. 2; opposite
3. ground
4. S
5. 20
6. \(1s^{2}2s^{2}2p^{6}3s^{2}\)
7. \([Ar]3d^{10}4s^{2}4p^{4}\)