4Ho+3O2→2Ho2O3{\displaystyle {\rm {4Ho+3O_{2}\to 2Ho_{2}O_{3}}}}
2Ho(s)+3F2(g)→2HoF3(s){\displaystyle {\rm {2Ho_{(s)}+3F_{2_{(g)}}\to 2HoF_{3_{(s)}}}}}
2Ho(s)+3Cl2(g)→2HoCl3(s){\displaystyle {\rm {2Ho_{(s)}+3Cl_{2_{(g)}}\to 2HoCl_{3_{(s)}}}}}
2Ho(s)+3Br2(g)→2HoBr3(s){\displaystyle {\rm {2Ho_{(s)}+3Br_{2_{(g)}}\to 2HoBr_{3_{(s)}}}}}
2Ho(s)+3I2(g)→2HoI3(s){\displaystyle {\rm {2Ho_{(s)}+3I_{2_{(g)}}\to 2HoI_{3_{(s)}}}}}
2Ho(s)+3H2SO4(aq)→2Ho(aq)+3+3SO4(aq)2−+3H2(g){\displaystyle {\rm {2Ho_{(s)}+3H_{2}SO_{4_{(aq)}}\to 2Ho_{(aq)}^{+3}+3SO_{4_{(aq)}}^{2-}+3H_{2_{(g)}}}}}