Simple question on water's autoionization

[zut212]

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A glass of pure water sits at room temperature. Which of the following is true:
A. There is about one hydrated H+ for every one billion water molecules in the glass.
D. The total number of hydrated H+ and OH- ions exceeds the total number of water molecules.












ANS: D. Their explanation is - "the equilibrium for the autoionization lies far to the left." . IMHO, the total number of H+ and OH- is MUCH MUCH less than that of the H2O, and so I think that this is an error.

 

[ilovemcat]

A glass of pure water sits at room temperature. Which of the following is true:
A. There is about one hydrated H+ for every one billion water molecules in the glass.
D. The total number of hydrated H+ and OH- ions exceeds the total number of water molecules.

ANS: D. Their explanation is - "the equilibrium for the autoionization lies far to the left." . IMHO, the total number of H+ and OH- is MUCH MUCH less than that of the H2O, and so I think that this is an error.

That must be an error. The ionization of water is extremely low (Kw = 1x10^-14). That in itself would tell you that there's much more water than either hydronium or hydroxide ions combined. Where'd this question come from?

 

[zut212]

this question comes from Exam Kracker's 1001 questions for chemistry, and it's question 772.

I knew that I was right. Thanks.

 

[golgiapparatus88]

EK1001 books seem to have a large amount of errors.

 

[sangria1986]

EK1001 books seem to have a large amount of errors.

Exam krakers sucks. I wouldn't use it as a learning tool much. I mean I value the biology ek book-but aside from that it's really useless