Recent content by alex5d1

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    Calculate CO2 for Water Equilibrium at pH 7.2

    Hi Borek, That calculation was correct! many thanks for your assistance. One more question, how do I calculate this one?: Lime (calcium hydroxide) is used in softening. How much lime (mmol/L) needs to be dosed in the softening step?
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    Calculate CO2 for Water Equilibrium at pH 7.2

    Sorry for my typo's in the units. The question as I understand it is to obtain Carbonic acid equilibrium given the equilibrium pH = pHs = 7.2 Then: pHs = 7.2 = equilibrium of CO2 (= H2CO3 ) and HCO3- pHs = pK1 – log ([CO2] / [HCO3-]) pK1 = 6.45 @12C log ([CO2] / [HCO3-]) = -0.750 [CO2] /...
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    Calculate CO2 for Water Equilibrium at pH 7.2

    Well, after some research I came up with this, what do you think? pHs = 7.2 = equilibrium of CO2 (= H2CO3 ) and HCO3- pHs = pK1 – log ([CO2] / [HCO3-]) pK1 = 6.45 @12C log ([CO2] / [HCO3-]) = -0.750 log ([CO2] / [HCO3-]) = 0.178 [HCO3-] = 223/61 = 3.656 mol/L [CO2] = 0.178 * 3.656 = 0.650...
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    Calculate CO2 for Water Equilibrium at pH 7.2

    Sorry, I forgot to mention that this is a water treatment problem. Temperature is 12C. What formula is applicable?
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    Calculate CO2 for Water Equilibrium at pH 7.2

    Hi, I must calculate how much CO2 has to be removed from the water (pHs=7.2) to obtain equilibrium Given concentrations: HCO3-: 223 mg/L CO2: 60 mg/L pH: unknown SI: unknown What is meant by equilibrium? (ph=7?) Please advise how to tackle this problem