good effort, but for me, I never even had to look at the periodic table. Most problems didn't require me to look at the periodic table, or it only involved calculation with basic elements you are used to using all the time, like oxygen = 16amu, carbon = 12 amu , etc, etc.
Also, if you've done a lot of destroyer gen chem problems, atomic weight for basic/commonly used elements should already be in your head lol
Chlorine - 35.45amu?