Chemistry Test Unit 5 Flashcards
What is a chemical formula?
A formula telling you how many elements are in this compound and how many atoms of each element there are in this compound.
The names of each compound are divided by the __________.
Icpac
Difference between subscript and coefficient
*Subscript is on bottom right
*subscript applies only to element it’s near
*coefficient is in front of equation
*coefficient applies to all elements in the equation
What’s a polyatomic ion?
A charged molecule
How do we know the name of a polyatomic ion?
Table E
How many atoms in:
Mg(OH)*2
5
How many atoms in:
3Mg(OH)*2
15
How many atoms in:
Mg(MnO4)2
11
How many atoms in:
2Mg(MnO4)2
22
What’s the Empirical Formula and its usage?
It’s a ratio that’s used for ionic compounds
What’s a Molecular Formula and its usage?
It’s the actual amount and it’s used for covalent compounds aka molecules
How can we change the Empirical Formula into the Molecular Formula?
- Find mass
- Multiply by subscript
- Add
Molecular mass of CO*2
46
Molecular mass of C6H12O*6
180
Change the Empirical formula into molecular formula:
CH*4 Mass: 32
C2H8
Change the Empirical Formula into Molecular Formula:
CH*3 Mass: 30
C2H6
What will a covalent compound tell you?
The amount of each element in the compound
In Covalent Formulas, the _______ of each element determines the ___________.
- Prefix
- Subscript
List the 10 prefixes in covalent compounds.
Prefixes:
Mono
Di
Tri
Tetra
Petra
Hex’s
Hepta
Octa
Nona
Deca
Sulfur hexafluoride
SF*6
Dihydrogen Monoxide
H*2O
Criss-Cross Method:
- Symbols- Check up element symbols
- Oxidation State- Find the oxidation state of each element
- Criss-cross- oxidation state of one becomes the subscript of other (drop charges)
- Simplify- Make sure it’s in Empirical form.
What happens if one of the elements has more than one oxidation state?
Use the first oxidation state for the second element, and then the stock system for the first.
What happens if there is a polyatomic ion?
If there are three elements, or the compound does not end with ode, look up the formula on table E.
