Furthermore, they have higher melting points, hardnesses, and densities, and lower reactivities and solubilities in liquid ammonia, as well as having more covalent character in their compounds.
fˌɜːðɚmˈoːɹ, ðeɪ hæv hˈaɪɚ mˈɛltɪŋ pˈɔɪnts, hˈɑːɹdnəsᵻz, ænd dˈɛnsᵻɾiz, ænd lˈoʊɚ ɹɪɐktˈɪvᵻɾiz ænd sˌɑːljuːbˈɪlᵻɾiz ɪn lˈɪkwɪd æmˈoʊniə, æz wˈɛl æz hˌævɪŋ mˈoːɹ kˈoʊvələnt kˈæɹɪktɚɹ ɪn ðɛɹ kˈɑːmpaʊndz.