I'm supposed to make a black precipitate using only the following chemicals: copper sulfate(II), lead nitrate, acetic acid, barium chloride, sodium hydroxide, copper(II) carbonate, methanol, potassium permanganate, hydrochloric acid, hydrogen peroxide, magnesium sulfate, and potassium dichromate.
I know that solid sulfides (used in qualitative analysis) are typically black in colour, such as copper(II) sulfide, but I don't have any source of the sulfide ion here. Is it actually possible to make a black precipitate?