Supplemental Activities
Module: Atomic Theory
Section: Periodic Properties and
Trends
Periodic Table and Reactivity
Activity 1
1.
Consider lithium metal.
a. Why don’t we find lithium metal in its neutral atomic state in nature?
b. In what electron configuration would you expect to find lithium metal?
c. Comment of the similarities between your answer for part b and the
electron configuration for helium.
2.
Why do groups/families tend to share common chemical behaviors? In your
explanation, discuss electron configurations and valence electrons.
Activity 2
1.
There is a radioactive isotope of strontium that can cause bone and blood cancers.
Why would strontium replace calcium in human bones (discuss valence electrons)?
2.
Find a noble gas and a common ion that are both isoelectronic with Sr2+and write
down the electron configuration that these species all share.
Activity 3
1.
Write down the charge the different groups tend to make when forming ions and
explain why:
a. Group IA –
b. Group 2A –
c. Group 5A –
d. Group 6A –
e. Group 7A –
f.
2.
Why?
How is the effective nuclear charge of an atom different than its nuclear charge?
Why is there a difference?
3.
How does effective nuclear charge change as you move down a group of elements?
As you move left to right across a period of elements?
4.
Consider the element calcium (Ca). What is the effective nuclear charge experience by
electrons in the following of Ca’s subshells?
a. 4s
b. 3p
c. 3s
d. 1s
5.
If a helium atom had an electron had one of its electrons excited from its 1s subshell to a
2s sbshell, what would be the ENC experienced by that electron?
6.
Consider an electron in the orbitals given and rank them from most attracted to the
nucleus to least attracted to the nucleus by comparing their effective nuclear charges that
they each experience.
(i) 3p in Mg (ii) 2p in O
(iii) 4s in Ca
(iv) 2s in K
Periodic Trends
Activity 1
1.
Arrange the following groups of atoms in order of decreasing size:
a. P, Sb, N, As –
b. Br, V, N, Ba –
2.
Which atom or ion in each of the following lists has the largest ionization energy:
a. Mg, Se, Ba –
b. Ca, Co, Se –
c. O2–, O, O2+ –
Activity 2
1.
Explain how shielding affects ionization energy and atomic radii.
2.
Why do noble gases have exceptionally low electron affinities and exceptionally high
ionization energies?
3.
Write the electron configuration for silver. Try to give at least one example of an ion that
would have an identical electron configuration.