Sodium thiosulphate ( $Na X_{2} S X_{2} O X_{3} \cdot 5 H X_{2} O$ , molar mass 248) is oxidised to different products by different oxidants. Which statements are correct?

AWith $I X_{2}$ (product $S X_{4} O X_{6} X^{2 -}$ ) its equivalent mass is 248
BWith excess $Cl X_{2}$ water (product $SO X_{4} X^{2 -}$ ) the n-factor per $S X_{2} O X_{3} X^{2 -}$ is 8
CWith excess $Cl X_{2}$ water (product $SO X_{4} X^{2 -}$ ) its equivalent mass is 31
DWith $I X_{2}$ one mole of thiosulphate reacts with one mole of $I X_{2}$

Answer: A, B, C

With iodine, S goes from +2 to +2.5 on average, so each

S X_{2} O X_{3} X^{2 -}

loses 1 electron: n = 1 and equivalent mass 248. With chlorine, each S goes from +2 to +6, giving 8 electrons per ion, so n = 8 and equivalent mass 248/8 = 31. The

I X_{2}

ratio is 1

I X_{2}

: 2 thiosulphate, so D is wrong. A, B and C are correct.

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Sodium thiosulphate (NaX2​SX2​OX3​⋅5HX2​O, molar mass 248) is oxidised to different products by different oxidants. Which statements are correct?

Answer: A, B, C

More questions on Redox titration calculations

Sodium thiosulphate ( $Na X_{2} S X_{2} O X_{3} \cdot 5 H X_{2} O$ , molar mass 248) is oxidised to different products by different oxidants. Which statements are correct?