Milkeh_Moo
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please can someone help me with how to go about this question,

16.0g of and impure sample of potassium hydroxide was dissolved in water and made up to 1.0dm3 in a volumetric flask. If 25cm3 of this solution required 50cm3 of 0.05 moldm-3 sulphuric acid for neutralisation, calculate the percentage purity of the potassium hydroxide (assuming that the impurities are neutral substances)

2KOH + H2SO4 goes to K2SO4 + 2H2O

I would be very grateful for any help at all
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charco
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(Original post by Milkeh_Moo)
please can someone help me with how to go about this question,

16.0g of and impure sample of potassium hydroxide was dissolved in water and made up to 1.0dm3 in a volumetric flask. If 25cm3 of this solution required 50cm3 of 0.05 moldm-3 sulphuric acid for neutralisation, calculate the percentage purity of the potassium hydroxide (assuming that the impurities are neutral substances)

2KOH + H2SO4 goes to K2SO4 + 2H2O

I would be very grateful for any help at all
1. Calculate the moles of sulphuric acid in 25ml and then scale up to 1000ml.
2. From (1) use the equation coefficients to work out the moles of KOH
3. From (2) Calculate the mass of this number of moles of KOH
4. Compare with the actual mass to get purity. %purity = 100 * actual mass/theoretical mass
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Nafas
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Hi every body

you can use this formula :
Cm*V=mg KOH/56
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charco
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(Original post by Nafas)
Hi every body

you can use this formula :
Cm*V=mg KOH/56
necrophiliac alert.
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