Counting Atoms
What does a subscript indicate?
How many atoms of an element there are
Name the following compound: Ba3P2
Barium phosphide
Octacarbon decahydride
Why do you have to balance equations?
There must be the same amount of each element of either side because matter cannot be created or destroyed (Law Conservation of Mass).
Why do elements create bonds?
To become stable and reach a stable octet with 8 valence electrons
What does a coefficient indicate?
How many molecules of the compound there are.
The cation is the metal & the anion is the nonmetal
When drawing covalent compounds, you need to draw the structural formula using lines to indicate bonds. How many electrons are shared between a single line, double line, and triple line?
single= 1 pair (2 electrons)
double= 2 pairs (4 electrons)
triple= 3 pairs (6 electrons)
What type of chemical is the following:
2Fe2O3 + 3C --> 4Fe + 3CO2
Single replacement
What is an isomer?
Isomers are compounds that have the same chemical formula but different chemical structures.
How many hydrogens are in the following compound?
C2H4(CH3COOH)
H= 8
Name 3 properties of ionic compounds
Made of metal and non metal
Make crystal lattices (solid at room temp)
Have high melting and boiling points
Create electrolytes when dissolved
Bonded together by electrostatic attraction due to gain or lose of electrons
Can conduct electricity
Name 3 properties of covalent compounds.
Made of 2 non metals
Share electrons to create bond
Have low melting and boiling points
Flammable
Brittle
Solid, liquid, or gas at room temp
Does not create electrolytes when dissolved
What type of reaction is shown in the following equation?
2KClO3 --> 2KCl + 3O2
Decomposition
What is an alloy and name 2 of them.
Alloys are solutions of metals. Mixed metals Brass, pewter, bronze, stainless steel.
Used because they are stronger!
How many atoms of each element are in the following compound:
2Mn2(Cr2O7)3
Mn= 2 X 2 = 4 total
Cr= 2 X 3 = 6 X 2 = 12 total
O=7 X 3 = 21 X 2 = 42 total
Iron (II) phosphate
Fe3(PO4)2
Write the formula for the following compound.
Pentaiodine heptafluoride
I5F7
What are always the products in a combustion reaction?
Carbon dioxide and water
What is unique about metallic bonds? What property does this allow them to have?
They create a sea of electrons when they bond together and this allows them to conduct electricity easily.
How many total atoms are in the following compound:
3V2(S2O3)4
V= 2 X 3= 6
S= 2 X 4= 8 X 3 = 24
O= 3 X 4 = 12 X 3 = 36
TOTAL= 66 total atoms
Draw an ionic compound between Cobalt (III) and Oxygen
Hint: Find the chemical formula first to know how many of each element there are in the compound.
Formula: Co2O3
Draw a covalent compound with the elements Antimony (Sb) and Fluoride (F)
Chemical Formula: SbF3
Balance the following equation and identify what type of reaction it is showing:
NH3 + O2 --> H2O + N2
Type: Single Replacement
4NH3 + 3O2 --> 6H2O + 2N2