1a) anion and S-2
1b) cation and Al+3
1c) anion and N-3
1d) cation and Ca+2
Answer:
The concentration is 
Explanation:
From the question we are told that
The absorbance is 
The length is 
Generally absorbance is mathematically represented as

where
is the molar absorptivity of FeSCN2 with a value 
and
is the equilibrium concentration of FeSCN2
So

substituting values


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