The concentration profile below represents a change to the above equilibrium system at time $t_1$:
The following concentrations are represented:
- $[Fe(SCN)]^{2+}$
- $[Fe^{3+}]$
- $[SCN^-]$
Which one of the following would account for the changes in concentration at time $t_1$?
A - VCE - SSCE Chemistry - Question 7 - 2012 - Paper 1
Question 7
The concentration profile below represents a change to the above equilibrium system at time $t_1$:
The following concentrations are represented:
- $[Fe(SCN)]^{2+}$... show full transcript
Worked Solution & Example Answer:The concentration profile below represents a change to the above equilibrium system at time $t_1$:
The following concentrations are represented:
- $[Fe(SCN)]^{2+}$
- $[Fe^{3+}]$
- $[SCN^-]$
Which one of the following would account for the changes in concentration at time $t_1$?
A - VCE - SSCE Chemistry - Question 7 - 2012 - Paper 1
Step 1
A. the addition of SCN^-
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Answer
The addition of SCN^- increases the concentration of thiocyanate ions in the system. According to Le Chatelier's Principle, this will shift the equilibrium to the right, forming more of the complex ion [Fe(SCN)]2+ while decreasing the concentration of Fe3+ as it reacts with the added SCN−. This explains the observed changes in concentration at time t1.