Loading presentation...

Present Remotely

Send the link below via email or IM


Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.


How to Write Ionic Formulas

No description

Isabel Krause

on 12 December 2010

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of How to Write Ionic Formulas

Writing Ionic Formulas There are a series of simple steps to follow when writing Ionic Formulas.
With these steps, writing the formulas will become easy and simple. Always Remember Your charges Anions add -ide to their original name (ie. Bromine becomes bromide) Definitions- Anion- Negatively charged Ion
- Cation- Positively charged Ion To write the Cation first, then the Anion Cross Method Steps: 1. Write the Cation first, then the Anion
2. Cross the charges between ions to become subscripts- the charge of the cation becomes the subscript of the Anion and vice versa
- if there is no subscript, it is assumed to be one
3. Reduce Example- Lets combine Magnesium with Chlorine Mg Cl +2 -1 (We know that Magnesium would become Mg because it is in Group 2A. In order to become stable,
Magnesium drops 2 electrons, giving it 2 more protons (+2) than electrons in its Ionic Form). +2 (We Know that Chlorine would become Cl because It is in Group 7A. In order to become stable, Chlorine gains 1 electron, giving it one more electron (-1) than protons in its Ionic form). -1 Mg Cl +2 -1 New Formula= MgCl 2 (Any negative number become positive when becoming a subscript) (The -1 turns to a positive one, but writing the number 1 is unnecessary because it just signifies that there is 1 of that element present, and we already know that). Example- (Reducing)--Lets combine Hg with O +2 -2 Hg O +2 -2 The twos cancel out and you are left with one of each molecule HgO Now, this is where it gets more complex. Lets write the formulas for polyatomic Ions: Use parenthesis around polyatomic ions Example- Let's combine Ammonium with Phosphate NH PO 4 +1 4 -3 (NH ) PO 4 3 4 The end product is 3 Ammonium ions and one Phosphate Naming Ionic Compounds When naming a compound...... Name the Cation first, then the Anion Monatomic Cation keep their element name Monatomic anions (nonmetals) change their suffix to -ide If there is more than one form of the ion, use Romal Numerals to specify which one is in the compound If the compound contains a polyatomic ion, simply name the ion Example- NaBr Sodium Bromine Since Bromine is an ion and a nonmetal, the suffix changes to -ide Sodium Bromide Example- Ca Cl 2 Calcium Chlorine suffix changes to -ide Calcium Chloride Example- K SO 2 4 In order to name a polyatomic atom correctly, it helps if you do the Cross method backwards. K (SO ) 2 4 1 End products--- K +1 SO 4 +2 - The formula has to consist of a Cation first, and then an Anion so we know that the Charge on K has to be +1 and the charge on SO has to be -2. - Potassium Sulfate 4
Full transcript