When phosphine is bubbled through a solution of silver nitrate $\mathrm{\_\_\_\_\_\_\_\_\_\_\_\_}$ is precipitated.

An aqueous solution of phosphine decomposes in the presence of light into red phosphorus and hydrogen. ... When passed through aqueous metallic salt solutions such as copper sulphate, silver nitrate, and mercuric chloride, phosphine gas precipitates the corresponding metal phosphides.

3AgNO₃​​+PH₃​​→Ag₃​P​↓+3HNO_3​​