It displays the +1 oxidation state that all the known alkali metals display, and thallium compounds with thallium in its +1 oxidation state closely resemble the corresponding potassium or silver compounds stoichiometrically due to the similar ionic radii of the Tl+ (164 pm), K+ (152 pm) and Ag+ (129 pm) ions.
ɪt dɪsplˈeɪz ðə plˈʌs wˈʌn ˌɑːksɪdˈeɪʃən stˈeɪt ðæt ˈɔːl ðə nˈoʊn ˈælkəlˌaɪ mˈɛɾəlz dɪsplˈeɪ, ænd θˈæliəm kˈɑːmpaʊndz wɪð θˈæliəm ɪn ɪts plˈʌs wˈʌn ˌɑːksɪdˈeɪʃən stˈeɪt klˈoʊsli ɹᵻzˈɛmbəl ðə kˌɔːɹɪspˈɑːndɪŋ pətˈæsiəm ɔːɹ sˈɪlvɚ kˈɑːmpaʊndz stˌoʊɪkɪoʊmˈɛtɹɪkli dˈuː tə ðə sˈɪmɪlɚɹ aɪˈɑːnɪk ɹˈeɪdɪˌaɪ ʌvðə tˌiːˈɛl plˈʌs wˈʌnhˈʌndɹɪd sˈɪksti fˈoːɹ pˌiːˈɛm, kˈeɪ plˈʌs wˈʌnhˈʌndɹɪd fˈɪfti tˈuː pˌiːˈɛm ænd ˈæɡ plˈʌs wˈʌnhˈʌndɹɪd twˈɛnti nˈaɪn pˌiːˈɛm ˈaɪɑːnz.