1. CaS CALCIUM SULFIDE Metal (calcium), non-metal (sulfide)
Calcium is group 2 so it has +2 charge
Sulfide is group 6 so it has a -2 charge
Ions are in a 1:1 ratio
So the chemical formula is:
CaS

2. KBr Potassium Bromide Metal (potassium) and non-metal (Bromide)
Potassium is group 1 so it has +1 charge
Bromide is group 7 so it has a -1 charge
Ions are in a 1:1 ratio
KBr

3. Fe2S3 Iron (III) Sulfide Metal (Iron) and a non-metal (sulfide)
Using stock system iron has a +3 charge
Sulfide is in group six has -2 charge
The ions exist in a 2:3 ratio
Fe2S3

4. MgI2 Magnesium Iodide Metal (magnesium) and non-metal (Iodide)
Magnesium is in group two so it has +2 charge
Iodide is in group seven so it has -1 charge
The ions exist in 1:2 ration
MgI2

5. LiF Lithium Fluoride Metal (lithium) and non-metal (Fluoride)
Lithium is group 1 so it has +1 charge
Fluoride is group 7 so it has a -1 charge
Ions are in a 1:1 ratio
LiF

6. FeCl3 Iron (III) Chloride Metal (Iron) and a non-metal (chloride)
Using stock system iron has a +3 charge
Chloride is in group seven has -1 charge
The ions exist in a 1:3 ratio
FeCl3

7. Zn3(PO4)2 Zinc Phosphate Metal (Zinc) and a polyatomic ion (Phosphate)
Zinc is transition metal that only forms a +2 ion
Phosphate is the polyatomic PO4-3
Ions exist in 3:2 ration
Zn3(PO4)2
Note the use of parentheses around the phosphate, it is because you need two of the whole polyatomic ion

8. Ammonium Nitrate
While this appears to be a molecule, as there are no metals, ammonium is the one polyatomic cation that you should know
Ammonium NH4+ has a +1 charge
Nitrate NO3- has a -1 charge
Ions are in a 1:1 ratio
NH4NO3

9. Al(OH)3 Aluminum Hydroxide
This is a metal (aluminum) and the polyatomic ion hydroxide
Aluminum is in group 3 and has a +3 charge
Hydroxide OH- has a -1 charge
Ion exist in a 1:1 ratio
Al(OH)3
Note the use of parentheses around the hydroxide, it is because you need two the whole polyatomic ion

10. Cu(H3CCOO)2 Copper(II) acetate
This is a metal (copper) and the polyatomic ion acetate
Using the Stock System copper has a +2 charge
The polyatomic ion acetate has a -1 charge
The ions exist in 1:2 ration
Cu(H3CCOO)2
Note the use of parentheses around the hydroxide, it is because you need two of the whole polyatomic ion
Also of note the acetate ion often shows up written different way, you need to be able to handle this

11. PbSO4 Lead(II) Sulfate Metal (lead) and the polyatomic ion sulfate
Using the Stock System lead has a +2 charge
Sulfate SO4-2 has a -2 charge
The ions exist in a 1:1 ratio
PbSO4

12. Dihydrogen Sulfide
Molecule convention because there are two non-metals
There are 2H
The is 1S,
H2S

13. Ca3P2 Calcium Phosphide Metal (calcium) and non-metal (phosphide)
Calcium is in group two so it has +2 charge
Phosphide is in group five so it has -3 charge
Ion exist in 3:2 ratio
Ca3P2

14. Fe2O3 Iron(III) Oxide Metal (Iron) and a non-metal (oxide)
Using stock system iron has a +3 charge
Oxide is in group six so it has -2 charge
The ions exist in a 2:3 ratio
Fe2O3

15. (NH4)3PO4 Ammonium Phosphate
While this appears to be a molecule, as there are no metals, ammonium is the one polyatomic cation that you should know.
Ammonium NH4+ has a +1 charge
Phosphate is the polyatomic PO4-3
Ion exist in 1:3 ratio
(NH4)3PO4
Note the use of parentheses around the ammonium, it is because you need three of the whole polyatomic ion

16. Sodium Carbonate
This is a metal (sodium) and the polyatomic ion carbonate
Sodium is group 1 so it has +1 charge
Carbonate CO3-2 has a -2 charge
Ions exist in a 2:1 ratio
Na2CO3

17. Tetrahydrogen DiNitride
Two non-metals so we use molecule naming convention
Tetrahydrogen so there are 4 H
Dinitirde so there are 2 N
H4N2
Hydrazine would be a acceptable name for this as well, as that is what is commonly know as.

18. Mg(NO3)2 Magnesium Nitrate
Metal (magnesium) and the polyatomic ion (nitrate)
Magnesium is in group two so it has +2 charge
Nitrate NO3- has a -1 charge
The ratio of ions is 1:2
Mg(NO3)2

19. Cu2SO4 Copper(I) Sulfate
This is a metal (copper) and the polyatomic ion sulfate
Using the Stock System copper has a +1 charge
Sulfate SO4-2 has a -2 charge
The ions exist in 2:1 ratio
Cu2SO4

20. Trihydrogen MonoNitride
Two non-metals so we use molecule naming convention
Trihydrogen so there are 3 H
Mononitride so there is 1 N
H3N
A common name for this compound is ammonia (You will need to learn this when we get to acid and bases in Unit 4).

21. Potassium Chromate K2CrO4
Made of a metal (potassium) and the polyatomic ion (chromate).
Potassium is group 1 so it has +1 charge
Chromate CrO4-2 has a -2 charge
Potassium Chromate

22. Gold(III) chloride AuCl3
Made of a metal (gold) and a non-metal (chloride)
Use stock system for gold(III)
Chloride is in group 7 so it has -1 charge
Gold(III) chloride

23. H2O2 H2O2 Molecule convention because there are two non-metals
Use Di because there are 2 H.
Use Di because there are 2 O.
H2O2
This compound has a common name of hydrogen peroxide

24. Beryllium Hydroxide Be(OH)2
Made of metal (beryllium) and the polyatomic anion hydroxide
Beryllium is a in group 2 so it has a +2 charge
Hydroxide OH- has a -1 charge
Ion ratio is 2:1
Beryllium Hydroxide

25. Ammonium Nitride (NH4)3N
While this appears to be a molecule, as there are no metals, ammonium is the one polyatomic cation that you should know.
Ammonium NH4+ has a +1 charge
Nitride is in group five so it has -3 charge
Ammonium Nitride

26. Iron(III) nitrate Fe(NO3)3
Made of metal (iron) and the polyatomic ion nitrate
Must use stock system as iron(III) has a +3 charge
The polyatomic anion nitrate as a -1 charge
Ion ratio is 1:3
Iron(III) nitrate

27. P2O5 Molecule convention because there are two non-metals
Use Di because there are 2 P.
Use Pent because there are 5 O.
Diphosphorus pentoxide

28. AgNO3
Made the a metal (silver) and the poly-atomic ion nitrate
Silver has a +1 charge
Nitrate anion NO3- has a -1 charge
Ion ratio is 1:1
Silver nitrate

29. Ammonium sulfite (NH4)2SO3
While this appears to be a molecule, as there are no metals, ammonium is the one polyatomic cation that you should know.
NH4+ is the polyatomic ion ammonium which has +1 charge
The sulfite SO3-2 polyatomic ion has a -2 charge
Ion ration is 2:1
Ammonium sulfite

30. Barium Sulfate BaSO4 This is a metal and the polyatomic ion sulfate
Barium is a in group 2 so it has a +2 charge
Sulfate SO4-2 has a -2 charge
Ion ratio is 1:1
Barium Sulfate

31. LiC2H3O2
This is a metal and the polyatomic anion acetate
Lithium is group 1 metal which has +1 charge
The polyatomic ion acetate has a -1 charge
The ion ratio is 1:1
Lithium acetate
Also of note the acetate ion often shows up written different way, you need to be able to handle this

32. Calcium hydrogen carbonate
Ca(HCO3)2
Made of a metal calcium and the polyatomic anion hydrogen carbonate
Calcium is a in group 2 so it has a +2 charge
The polyatomic anion hydrogen carbonate has a -1 charge
The ion ratio is 1:2
Calcium hydrogen carbonate
The hydrogen carbonate anion is often called bicarbonate (so the name would be calcium bicarbonate)

33. Potassium Chloride KCl
This made of a metal (potassium) and non-metal (chloride)
Potassium is group 1 so it has +1 charge
Chloride is group 7 so it has a -1 charge
The ratio of ions is 1:1
Potassium Chloride

34. Magnesium Chloride MgCl2
This is made of metal (magnesium) and a non-metal (chloride)
Magnesium is in group 2 so it has +2 charge
Chloride is in group 7 so it has -1 charge
The ion ratio is 1:2.
Magnesium Chloride

35. Fe2O3
This made of a metal (iron) and non-metal (oxide)
Must use the stock system, Fe(III) which has a +3 charge (You know it is iron(III), from the number of oxide anions
Oxide is group 6, so it has a -2 charge
Ion ration is 2:3
Iron(III) oxide

36. LiBr
This made of a metal (lithium) and non-metal (bromide)
Lithium is group 1 so it has +1 charge
Bromide is group 7 so it has a -1 charge
The ratio of ions is 1:1
Lithium Bromide

37. Mercury(II) Chloride HgCl2
Made of metal (mercury) and a non-metal (chloride)
Mercury(II) uses the Stock System so it has +2 charge
Chloride is in group 7 so it has -1 charge
Ion ratio is 1:2
Mercury(II) Chloride

38. Carbon tetrabromide CBr4
Molecule convention because there are two non-metals
There is 1 C, but since it is the first element we drop the mono
There are 4 Br so use Tetra
Carbon tetrabromide

39. Sulfur Hexaflouride SF6
Molecule convention because there are two non-metals
There is 1 S, but since it is the first element we drop the mono
There are 6 F so use hexa
Sulfur Hexaflouride

40. Tetrasulfur tetraphosphide
Molecule convention because there are two non-metals
There are 4 S, so Tetra
There are 4 p so use Tetra
Tetrasulfur tetraphosphide

41. Iron(III) Phosphate FePO4
Metal (Iron) and a polyatomic ion (Phosphate)
Must use the stock system, Fe(III) which has a +3 charge (You know it is iron(III), from the phosphate ion).
Ion ratio is 1:1
Iron(III) Phosphate

42. Calcium Nitrite Ca(NO2)2
Made of the metal calcium and the polyatomic ion nitrite
Calcium is in group 2 so it has +2 charge
The nitrite anion NO2- has a -1 charge
The ion ratio is 1:2
Calcium Nitrite

43. Iodine tetraflouride IF4
Molecule convention because there are two non-metals
There is 1 I, but since it is the first element we drop the mono
There are 4 F so use Tetra
Iodine tetraflouride

44. Sn(CO3)2 Made the metal tin, and the polyatomic anion carbonate
Tin uses the stock system and has +4 charge (which you know from the two carbonates)
The polyatomic ion carbonate CO3-2 has -1 charge
Tin(IV) carbonate

45. Magnesium Bromide MgBr2
This is made of metal (magnesium) and a non-metal (bromide)
Magnesium is in group 2 so it has +2 charge
Bromides in group 7 so it has -1 charge
The ion ratio is 1:2.
Magnesium Bromide

46. NaCH3CO2
This is a metal and the polyatomic anion acetate
Sodium is group 1 metal which has +1 charge
The polyatomic ion acetate has a -1 charge
The ion ratio is 1:1
Sodium acetate
Also of note the acetate ion often shows up written different way, you need to be able to handle this

47. AgCl
Made the a metal (silver) and the poly-atomic ion nitrate
Silver has a +1 charge
Chloride is in group 7 so it has -1 charge
Ion ratio is 1:1
Silver chloride

48. Phosphorus pentachlouride
PCl5
Molecule convention because there are two non-metals
There is 1 P, but since it is the first element we drop the mono
There are 5 Cl so use Penta
Phosphorus pentachlouride

49. Dichlorine heptoxide Cl2O7
Molecule convention because there are two non-metals
The are 2 Cl so use Di
There are 7 O so use hepta
Dichlorine heptoxide

50. Dihydrogen monoxide H2O
Molecule convention because there are two non-metals
There are 2H so use Di
The is 1 O, so use mono
Dihydrogen monoxide
More commonly known as water.