A50.0 ml sample of a cu(no3)2 solution, which
is a blue solution, and a naoh solution, which is
colorless, are combined forming a blue cu(oh)2
(molar mass 81.5) precipitate. the 0.815 g
precipitate is collected through filtration, and the
colorless filtrate is set apart. what is the
concentration of the original cu(no3)2 solution?
(a) 0.10 m
(b) 0.20 m
(c) 0.40 m
(d) the concentration of cu(no3)2 solution
cannot be determined because it was the
excess reactant.

in 1783 cavendish was working with his hydrogen gas and found that when he burned it and condensed the vapor it was water. this was very significant since it disproved the greek theory of elements completely since water was not a simple substance but the product of two gases. it was lavoisier who hearing of the experiment gave cavendish's gas the name hydrogen ("water-producer") and added that hydrogen burned by combining with oxygen and that water was a hydrogen-oxygen combination.

explanation:

so whats the answer tell me