Fifty years ago, when I got my chemistry degree, "cuprous nitrate" was the standard name for what is now called, using the Stock System, "copper(I) nitrate". Its formula is CuNO3.
Actually, the answer Cu(NO3)2 is incorrect for cuprous nitrate. Cu(NO3)2 is in fact cupric nitrate. Cuprous nitrate is represented as CuNO3 alone.
Cuprous nitrtate is copper(I) nitrate. CuNO3. The copper is in oxidation state '1' The more usual form is cupric nitrate that is copper(II)nitrate. Cu(NO3)2 The copper is in oxidation state '2'. NB THe 'cuprous/cupric' comes the Latin name for copper , which is 'cuprum'.
The name of the formula CuNO3 is copper(II) nitrate.
A double replacement takes place. And a precipitate is formed called AgCl. It is solution on CuNO3.
The cuprous sulfide - Cu2S - is black.
Cu(NO3)2 and CuNO3 cupric (Cu-II) and cuprous (Cu-I) nitrate
a cuprous ion has 28 electrons.
The chemical formula for cuprous fluoride is CuF.
"Cuprous" is an archaic term for what today is called copper (I), Cu+1.
The chemical formula for cuprous arsenide is Cu3As.
Cuprous salts are typically white or pale yellow in color.
The charge on cuprous ion is +2. It is written as Cu2+.