(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A sample of hard water contains 305 ppm of HCO3- ions. What is the minimum mass of CaO required to remove HCO3- completely from 1 kg of water sample?

2. Relevant equations

Ca 2+ + 2HCO3 + CaO = 2CaCO3 + H2O

3. The attempt at a solution

Since the HCO3- ions are 305 parts per million, it can be assumed that there are 0.305 g of the ions in 1 kg (or 1 L as the density is 1) of water. (I don't know if this assumption is correct)

If I use the equation as above, then I get 0.1525 g of CaO which is not correct.

I think that the whole trouble is with the ppm part. Can someone give me a clue?

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# Homework Help: Amount of CaO required to removed HCO3- from 1 kg of hard water

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