Chapter 9

38 views6 pages
Published on 16 Oct 2011
Chapter 9: the periodic Table and Some Atomic Properties
- The basis of the PT is the e’ configuration of the element s
9-1 classifying elements: the Periodic law and the PT:
Periodic law: when elements are arranged in order of increasing atomic mass,
certain sets of properties recur periodically
- Molar volume: atomic mass of an element divided by the density of its solid form
- Periodic law was based on molar volume ( atomic volume)
- Results represented by a graph of atomic volume against atomic mass ( molar
volume against atomic number)
- Argon was the first noble gas discovered
- Restated periodic law: similar properties recur periodically when elements are
arranged according to increasing atomic number
- Page 343 description of periodic table!
9-2 metals and non-metals and their ions:
- Metals good conductors of heat/electricity, malleable, ductile, moderate-high MP
- Non-metals non-conductors of heat/electricity , non-malleable, brittle solid or gas
at room temp
- Metalloids look like metals, behave like metals but have some non-metallic
properties as well
- Physical and chemical properties of elements are determined largely by its e’
config, valence electronic shell
Noble gases:
- Atomics of the noble gases have the max # of e’ permitted in the valence shell
- The s block , Al tend to lose enough electrons to acquire the e’ config of the noble
Main-group metal ions:
- Al is the only p-block metal that forms an ion with a noble gas config Al3+
Main-group non-metal ions:
- Atoms of group 17 & 16 the most active non-metals
Unlock document

This preview shows pages 1-2 of the document.
Unlock all 6 pages and 3 million more documents.

Already have an account? Log in
- Non-metals will gain a single e spontaneously , but energy is required to force it to
accept more than one
- Necessary energy is often supplied by: attraction between positive and negative
Transition metal ions:
- Electron config for: Ti [Ar] 3d24s2 Ti2+ [Ar]3d2
- E’ config with half-filled or filled d or f sub shells have a special stability
9-3 sizes of atoms and ions:
Atomic radius:
- The probability of finding an electron decreases with increasing distance from the
nucleus, but no where does the probability falls to zero.
- Effective atomic radius: distance from the nucleus within 95% of all the electron
charge density found
- Covalent radius: one half the distance between the nuclei of two identical atoms
joined by a single covalent bond
- Ionic radius: based on the distance on the distance between the nuclei of ions joined
by an ionic bond
- Metallic radius: one half the distance between the nuclei of 2 atoms in contact in
the crystalline solid metal
- In a solid sample of noble gas, the distance between the centers of the
neighbouring atomic called van del waals radius
1nm=1 * 10-9 m; 1pm = 1* 10-12 m; 1nm= 1000pm
Screening and penetration:
- Penetration was described as a gauge of how close and e’ gets to the nucleus
- S e’ with their extra humps of probability close nuclear penetrate better than d e’
- Screen or shielding reflects how an outer e’ is blocked from the nuclear charge by
the inner e’
- The core e’ shield the outer shell e’ from the full attractive force of the nucleus
- Effective nuclear charge Zeff
Zeff=Z - S S= # of inner e’ that shield an outer e’
Unlock document

This preview shows pages 1-2 of the document.
Unlock all 6 pages and 3 million more documents.

Already have an account? Log in

Get OneClass Notes+

Unlimited access to class notes and textbook notes.

YearlyBest Value
75% OFF
$8 USD/m
$30 USD/m
You will be charged $96 USD upfront and auto renewed at the end of each cycle. You may cancel anytime under Payment Settings. For more information, see our Terms and Privacy.
Payments are encrypted using 256-bit SSL. Powered by Stripe.