While going via my AP chem prep book again, I came throughout questions asking about the color of specific aqueous options. For example:

Which of the following substances will create a colormuch less aqueous solution?

A) $ceZn2(NO3)2$B) $ceCu(SO4)$C) $ceK2Cr2O7$D) $ceCo(NO3)2$

I recognize that zinc compounds are primarily colormuch less, so I picked that (and also it was correct), yet I have no idea just how to predict the colors of the remainder of the compounds.

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So, to answer this question (and inquiries similar to this), would I should use pure memorization of the widespread facets that create color?

If so, wright here can I uncover indevelopment about these compounds and also the color they produce?


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There is no simple way to predict beforehand also as far as I know. This is a general expertise type of chemisattempt question, you will have to recognize or memorize the colors of common anions and also cations. It will be a lot much easier, if you execute so group wise and understand the colors of the first row of shift facet ions.

Any object which absorbs a particular percent of visible light"s spectrum, will certainly appear colored to us. For colored solutions, we will always think about absorption of light in the visible region. So if you view a green solution, it is not showing green light, it is soaking up a details portion of the visible spectrum and the transmitted light appears green to us. Keep this concept in mind bereason the majority of students have this misconception.

You should recognize that sulfate ion is colorless however copper (II) ion is blue so many likely copper sulfate solution is blue. In component c, you should recognize the shade of potassium ion and also dichromate ion and also then guess the color. Do the continuing to be exercise for others.

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It will certainly be extremely difficult to predict if both ions are colored bereason it is not prefer that we are mixing two paints, a yellow paint via blue paint will show a green color. You will have to study the absorption spectrum of that salt. The theory of shade of ions and that of solids is rather complicated. It was developed by physicists. You deserve to begin from crystal area theory if you wish to watch just how the color of transition metal ions is explained yet I will not recommend that you check out it if you are in institution.