Easy periodic table question, pls help What are columns (up and down) of the periodic table called? How does the element’s column relate its number of valence electrons?

Fill in the blank chromium(iii) sulfate is a transition metal compound containing the metal chromium and the polyatomic ion sulfate.the oxidation state of chromium in this compound is , and the chemical formula of the compound is _ _ ( _ _ ) ._ chemical name chemical formula chemical name chemical formula acetate c2h3o2– nitrite no2– carbonate co32– ammonium nh4+ hypocarbonite co2− cyanide cn– hydrogen carbonate (bicarbonate) hco3– hydroxide oh– chlorite clo2– peroxide o22– hypochlorite clo– phosphate po43– chlorate clo3– hydrogen phosphate hpo42– perchlorate clo4– dihydrogen phosphate h2po4– hydronium h3o+ sulfate so42– permanganate mno4– hydrogen sulfate (bisulfate) hso4– nitrate no3– sulfite so32–