Dalam soal ini, yang harus diingat adalah tentang deret volta, dimana pereduksi atau reduktor paling kuat adalah yang memiliki nilai potensial elektroda paling negatif, atau berada paling atas (atas ke bawah) atau kiri (kiri ke kanan) dalam deret volta.
Dari soal ini, ditentukan posisi relatif dari unsur-unsur tersebut dalam deret volta.
Berdasarkan Reaksi 1, yaitu
![Error converting from MathML to accessible text.](data:image/png;base64,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)
Unsur P dapat mendesak unsur R, artinya unsur P merupakan reduktor sehingga posisinya dalam deret volta berada di sebelah kiri (Pakai kiri ke kanan) dari unsur R dengan jarak
.
Sehingga polanya menjadi
.
Reaksi 2, yaitu
![Error converting from MathML to accessible text.](data:image/png;base64,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)
Unsur S dapat mendesak unsur Q, artinya unsur S merupakan reduktor sehingga posisinya dalam deret volta berada di sebelah kiri dari unsur Q dengan jarak
.
Sehingga polanya menjadi
.
Reaksi 3, yaitu
![Error converting from MathML to accessible text.](data:image/png;base64,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)
Unsur R tidak dapat mendesak unsur Q, artinya unsur R merupakan reduktor lemah jika dibandingkan dengan unsur Q, sehingga posisinya dalam deret volta berada di sebelah kanan unsur Q dengan jarak
.
Sehingga polanya menjadi
.
Sehingga, jika digambarkan menjadi
.
Sehingga, berdasarkan gambaran tersebut diperoleh informasi bahwa urutan reduktor dari yang paling kuat ke yang lemah yaitu
.