Can the anion affect color of a solution

Yes

Explanation:Either the anion or the cation can be responsible for solution color. Some transition metals produce colored cations but there are plenty of colored anions such as chromate and permanganate. ... As they absorb this light we see the contrasting colour light coming through the solution and thus see it to be blue in colour.

because natural gas is colorless, odorless, and tasteless, distributors add mercaptan (a chemical that smells like sulfur) to give natural gas a distinct unpleasant odor (it smells like rotten eggs). they locate the types of rock that are likely to contain natural gas deposits.