Reorder the following so that they are a correct electron configuration for sulfur.

• 1s²

• 2s²

• 3p⁴

• 2p⁶

• 3s²

The ​ ​ (a)   states that electrons will fill the lowest energy levels first. The ​ (b)   states that we cannot know an electrons position and velocity at the same time. ​ (c)   states that every orbital must be singly occupied before any orbital is doubly occupied. The ​ (d)   states that two electrons occupying the same orbital will have opposite spins.

• Aufbau Principle
• Heisenberg Uncertainty Principle
• Hund's Rule
• Pauli Exclusion Principle

Each of the images is a violation of a rule. Which rule?

Groups:

(a) Hund's Rule

,

(b) Aufbau Principle

,

(c) Pauli Exclusion Principle

,

(d) This is a correct configuration

• 
• 
• 
• 
• 
• 
• 
• 

Which of these is the correct configuration for tin (Sn)?

• [Kr] 5s²3d¹⁰3f¹⁴5p⁴

• [Kr]5s²3d¹⁰4d¹⁴5p⁴

• [Kr]5s²3d¹⁰4f¹⁴5p²

• [Kr]5s²4d¹⁰5p²

Label the following segment.

a

b

c

number of electrons present

orbital

configuration

energy level

Why are all atomic masses not whole numbers?

• This is due to the mass of all the electrons in the atom.

• This is because of experimental error.

• This is because atomic masses are the weighted average of the masses of all naturally-occurring isotopes.

• This is due to binding energy of the atoms.

An isotope has three forms.  10% have a mass of 4 amu, 70% have a mass of 5 amu and 20% have a mass of 3 amu.  Average atomic mass will be closest to

• 2 amu

• 3 amu

• 4 amu

• 5 amu

24.1% of all the isotopes of a an element have a mass of 75.23 amu, 48.7% have a mass of 74.61 amu, and 27.2% have a mass of 75.20 amu.
What is the average mass of this element?

• 74.92 amu

• 15.01 amu

• 24.97 amu

• 64.51 amu

Which noble gas would be used for the configuration of osmium?

Which noble gas would be used for the configuration of titanium?