Not accepted by Duolingo :(
Right, they accept the kanji for green, they can accept 紫色 which is still being marked wrong (1.31.18), and still (2.13.18) sigh still (3.17.18).
And still (7.1.18). I've reported this one half a dozen times already. They'll get around to it eventually.
All these colors made me think of Kuroko no Basket
What does -iro mean at the end of colors?
"iro" = color :)
Is including "iro" at the end necessary?
No, it's not necessary to use "iro" with colors, with a few exceptions like 黄色 kiiro yellow, 灰色 haiiro gray, and 茶色 chairo brown.
I imagine it makes it clear you're talking about the color purple rather something with purple connotations. Kinda like how a "blue person" is sad, not actually blue.
is iro necessary? x2
紫色 is still not accepted as a good answer...
「紫」alone should be accepted, because it means purple