Chapter 3 printable lecture notes
Tro 4th ed
Section 3.1, Mixtures of Hydrogen and Oxygen
What are some uses of hydrogen and oxygen?
Is oxygen gas flammable?
Would you like to burn something in pure oxygen, and ignite hydrogen in air? That’s all coming up in
lab in a few weeks!
Section 3.2, Chemical Bonds
Ionic compounds are made of ________________________, which are charged ____________________________________.
Ionic compounds (like NaCl) are usually formed between __________________________________________________.
Ionic compounds are formed by the transfer of ___________________________________________.
The ionic bond is an electrostatic attraction between the __________________________________________________
View figure 3.2, look at the properties of the elements and the product, the arrangement of ions, and
the transfer of electrons.
Molecular compounds exist as individual _________________________________________________________.
Molecules stay intact:
_____________________________________________________________________________________________
Or _____________________________________________________________________________________________________________
Molecular formula: _____________________________________________________________
C6H12O6
Empirical formula: ______________________________________________________________
CH2O
Molecular Elements in Nature (know these)
___________________________________________________________________________________________________________________
The elements are: _____________________________________________________________________________________
This is their chemical state at normal surface of the Earth conditions.
Read 3.3 and 3.4 on your own – properties of compounds
Make sure you know the definition of polyatomic and formula unit.
Section 3.5, Chemical Bonds
Compounds and Molecules:
The chemical formula of a compound indicates
a. __________________________________________________________________________________________
b. __________________________________________________________________________________________
In formulas for ionic compounds:
a. __________________________________________________________________________________________
b. __________________________________________________________________________________________
Write formulas for compounds made of these ions:
Ba and Br _________________________________________
Na and S ______________________________________________
Mg and N _________________________________________
Fe3+ and SO42– ________________________________________
Cation (+ ion) name goes first
elemental cations are named as the ___________________________________________________
Anion (– ion) goes second
replace suffix of element with _____________________
GaAs gallium + arsenic = ________________________________________
Simple ionic compounds: name these:
BaBr2 ______________________________________________
Na2S ________________________________________________
Mg3N2 ______________________________________________
Ionic compounds with variable-charge metals
Some metals have variable charges that _______________________________________________________________________
The names of these compounds use a ________________________________________________________________________
Sn4+ is written as _________________________________________________________
What is the formula for tin(II) chloride? _________________________________________________
What is the name for?
CuO _______________________________________________ Cu2O _________________________________________________________
Polyatomic ions __________________________________________________________________
Section 3.6 Molecular Compounds and Acids
•
More metallic element’s name comes first
o Metallic character increases going down or left
o When in doubt, put carbon first, or oxygen last
•
Add “ide” to the 2nd element’s name
•
Use Greek prefixes to show how many atoms are in the compound
•
Drop one letter of “a-o” or “o-o”, but not “i–i”
o Example carbon monoxide, not carbon monooxide
Name:
N3Cl7 _________________________________________________ CBr4 ____________________________________________________
S2O5 ________________________________________________
Naming Inorganic Acids
Acids: a special class of compound with ______________________________________________________
Names of acids are related to the names of anions:
a. ____________________________________________________________________________________
b. ____________________________________________________________________________________
c. ____________________________________________________________________________________
For oxoanions (Cl, Br, and I oxoanions only)
Section 3.8, 3.9 Molar masses and formulas of compounds
Molar masses of compounds are the sum of all atoms
For all molar masses, _________________________________________________________________________
Calculate the molar mass of chromium(II) nitrate.
Chemical formulas can be made into conversion ratios. For each mole of iron(III) perchlorate, there
are _______________________________ moles of oxygen atoms
Examples:
How many moles of O are in one mole of Cr(NO3)2?
How many moles of O atoms are present in 168.0 g of Cr(NO3)2?
What mass (in g) of O is present in 168.0 g of Cr(NO3)2?
Section 3.9, and 3.10 How To Determine Formulas of Compounds
Mass percentage is the fraction, by mass, of one element in a compound.
What is the mass percent of sulfur in lithium sulfide?
Chemists must determine formulas for new compounds
Qualitative:_________________________________________________________
Quantitative: ________________________________________________________
Percent composition:
mass of element  mass of sample x 100%
Must use moles __________________________________________________________________________________________________
A compound consists of 0.5745 g silver (Ag) and 0.4255 g bromine (Br). What is the formula of the
compound?
A compound consists of 45.5% by mass Sn, plus Cl. What is the formula of the compound?
A sample of Vitamin C has mass percentages of 40.9% C 4.51% H
formula?
54.5% O. What is the empirical
Combustion analysis
A 2.000 g sample of a substance containing C, H, Li undergoes complete combustion to produce
5.500 g of CO2 and 2.526 g of H2O.
What is the empirical formula of this compound?
Section 3.11: Balancing equations
1. Write correct formulas for reactants and products, based on names or your knowledge of ions
2. Adjust subscripts only in step 1
3. Use coefficients in front of each substance
4. Balance elements in complex substances first
5. Balance polyatomic ions as a group if they stay as groups
6. If an element appears in 2 or more places on one side of arrow, balance last
Sr(s)
+
H2O (l) 
K2SO4(aq) +
C3H8 (g) +
Au(NO3)2
Sr(OH)2 (aq) +
Ba(OH)2(aq)
O2 (g) 
+
(NH4)3PO4
BaSO4 (s) +
CO2 (g) +

H2 (g)
KOH (aq)
H2O (g)
NH4NO3
+
Au3(PO4)2
Naming and formula practice
calcium fluoride
sodium oxide
aluminum sulfide
strontium nitride
iron(II) hydride
aluminum nitrite
lead (IV) phosphate
lithium oxalate
manganese(II) perchlorate
magnesium cyanide
Sodium hypochlorite
chromium(VI) hydrogen carbonate
tin(IV) hydroxide
zinc sulfite
Write proper formulas and names:
Na and N
Cu2+ and NO–
Co3+ and CO32–
K and CN–
Ca and PO43–
Sr and MnO4–
Zn and SO32–
Aluminum nitrate
dinitrogen octafluoride
Co2(CO3)3
Li2S
FeBr3
manganese(III) bromite
Ca(OH)2
AgC2H3O2
strontium hypoiodite
N2F4
PbHPO4