What are all the possible chemical formulas for- 1. cadmium and fluorine
2. vanadium and arsenic
3. rhenium and oxygen
4. lead and sulfur
5.titanium and nitrogen
6.palladium and chlorine
7.iridium and carbon
8.chromium and phosphorus

number 7 or 3,5

Explanation:

sana po makatulong po sa inyo

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.