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Chemistry question help

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Can someone please explain fully how you complete this question...:smile:


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Reply 1
First, find the number of moles of the Iodine solution (I2)...
n = cv = 0.005 x 0.0112 = 5.6x10^-5 mol

Due to molar ratios, the number of moles of SO2 is also 5.6x10^-5 mol (assuming nothing is in excess)...
SO2 : I2
1 : 1
5.6x10^-5 : 5.6x10^-5

Now find the mass of SO2...
m = n x gfm = 5.6x10^-5 x (32.1 + 16 + 16) = 3.5896x10^-3 g = 3.5896 mg

which gives us the concentration of SO2 being 3.596 mg per 100 cm3 (mg 100cm3^-1)
So, there must 10 x that amount in a litre (1000cm3)
=> concentration of sulphur dioxide present in the wine = 10 x 3.5896 = 35.896 = 35.9 mg l^-1

Hope this helped :wink:
ps. also please say if it doesn't match the answer XD
Reply 2
Thank you very much:smile::smile:


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