Chapter 5 Part 2

Chapter 5 Part 2 - Homework due today this is the last...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
Chemistry in the News: • Wildfires are currently raging in southern California • Chemical flame retardants can be extremely useful in fire fighting • Older retardants are now known to be toxic. Chemists have developed ‘green’ (environmentally friendly), polymer-based gels that are biodegradable and washable! • Homework due today – this is the last assignment before the exam in one week, which will be on chapters 4 and 5 • Homework answers and study guide for the exam are on the way ******************************************************************************** See article(s) # 19 – a CNN news article and one on the science of flame retardants
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Polyatomic Ions Polyatomic ions are groups of covalently bonded atoms with a charge. • Memorize this table
Background image of page 2
Writing Formulas Using Polyatomic Ions When writing formulas for compounds containing polyatomic ions, it may be necessary to use parentheses to denote the proper number of the ion. Example: calcium nitrate Ca 2+ NO 3 - Ca(NO 3 ) 2
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Naming Compounds with Polyatomic Ions When naming compounds with polyatomic ions, simply name the ions in order. Example: (NH 4 ) 2 SO 4 ammonium sulfate
Background image of page 4
Rules for Sketching Lewis Structures 1. Count valence electrons. 2. Sketch a skeletal structure. 3. Place electrons as lone pairs around outer atoms to fulfill the octet rule. 4. Subtract the electrons used so far from the total number of valence electrons. Place any remaining electrons around the central atom. 5. If the central atom lacks an octet, move one or more lone pairs from an outer atom to a double or triple bond to complete an octet. Ex. CHOF* * When in doubt, place least electronegative atom at the center, which is carbon in the above example. See next slide for EN scale. Also, C must have 4 bonds (see two slides ahead).
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Electronegativity is a measure of an atom’s attraction for the electrons in a bond.
Background image of page 6
Image of page 7
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/23/2009 for the course CHEMISTRY CH105 taught by Professor Armstrong during the Fall '07 term at BC.

Page1 / 36

Chapter 5 Part 2 - Homework due today this is the last...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online