The alkali metals dissolve slowly in liquid ammonia, forming ammoniacal solutions of solvated metal cation M+ and solvated electron e−, which react to form hydrogen gas and the alkali metal amide (MNH2, where M represents an alkali metal): this was first noted by Humphry Davy in 1809 and rediscovered by W. Weyl in 1864.
ðɪ ˈælkəlˌaɪ mˈɛɾəlz dɪsˈɑːlv slˈoʊli ɪn lˈɪkwɪd æmˈoʊniə, fˈɔːɹmɪŋ ˈæmoʊnˌɪækəl səlˈuːʃənz ʌv sˈɑːlveɪɾᵻd mˈɛɾəl kˈæɾaɪən ˈɛm plˈʌs ænd sˈɑːlveɪɾᵻd ᵻlˈɛktɹɑːn ˈiː mˈaɪnəs, wˌɪtʃ ɹɪˈækt tə fˈɔːɹm hˈaɪdɹədʒən ɡˈæs ænd ðɪ ˈælkəlˌaɪ mˈɛɾəl ɐmˈaɪd ˌɛmˌɛnˈeɪtʃ tˈuː, wˌɛɹ ˈɛm ɹˌɛpɹᵻzˈɛnts ɐn ˈælkəlˌaɪ mˈɛɾəl: ðɪs wʌz fˈɜːst nˈoʊɾᵻd baɪ hˈʌmfɹi dˈeɪvi ɪn wˈʌn θˈaʊzənd ˈeɪthˈʌndɹɪd nˈaɪn ænd ɹˌiːdɪskˈʌvɚd baɪ dˈʌbəljˌuː. wˈeɪl ɪn wˈʌn θˈaʊzənd ˈeɪthˈʌndɹɪd sˈɪksti fˈoːɹ.