1. ELEMENT RIDDLES 
1.If you get a part in the school play, you will be required to _________
Actinium
Iodine
2.What you call dinner for one ______

2. Group work
Looking at the covalent compounds below list 3 patterns you see in how the names are written.
dinitrogen trioxide
nitrogen trichloride
carbon disulfide

3. Patterns:
Both elements are non-metals
Ending is changed to ‘ide’
They have prefixes (Tell you how many of each there are)
mono, di, tri, tetra, penta, hexa, hepta, octa, nona, deca, you should know 1-6

4. Naming Covalent Compounds
Write the Names of Binary Covalent Compound
A binary covalent compound contains
two non-metal element.
Steps:
1. name the left element in the formula first.
2. name the second element, make sure the element name ends with the suffix ‘ide’
3. add a prefix to each element’s name to indicate the number of atoms of each element in the compound.
Example:
N2O3:
dinitrogen trioxide

5. Naming Covalent Compounds
carbon monoxide
The prefix “mono” is shortened to “mon” if it is placed before “oxide”.
Do not use a prefix when there is only one atom of the first element.

7. Example: NO
NO2
SO2
SO3

8. Try writing the formula for each covalent Compound.
Group work
Try writing the formula for each covalent
Compound.
Hint: disulfur decachloride is S2Cl10
dinitrogen trioxide
nitrogen trichloride
carbon disulfide
tetraphosphorus decaoxide
phosphorus pentabromide
Answers:
(a) N2O3
(b) NCl3
(c) CS2
(d) P4O10
(e) PBr5