Periodic Table

Periodic Table

Our learning outcome of Subtopic 3.1

Multiple Choice

Group was determine by the number of _________ .

• electrons

• valence electrons

• proton number

• nucleon number

Multiple Choice

Phosphorus and sulfur are in same Period because _____.

• they have same number of valence electrons

• they are in same group

• both of them are non metal

• their valence electrons are in same shell

This is a summary of the atomic radius of elements in Periodic Table.

The size of atom increase when going down the group. 

The size of atom decrease when across a period (not including transition element).

Factor Zeff use when explaining size of atom across a period. Use shielding effect to explain the size of atom down a group. 

Multiple Select

Which statement(s) is/are true?

• Be is smaller than Mg due to Zeff.

• Li is smaller than Na due to shielding effect.

• B is larger than C due to Zeff.

• Al larger than Si due to shielding effect.

As you can see the size of atoms in transition elements (light blue) does not change significantly.

That's it for this session. Will continue our lesson next week.