## lecture 1/13 topic

Christineg1G
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### lecture 1/13 topic

What did Dr. Lavelle mean in lecture 1 today when he said that 10^-12 is actually and would be correct if it were written as 10^-7 for the concentration of H3O+?

Brian_Ho_2B
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### Re: lecture 1/13 topic

Christineg1G wrote:What did Dr. Lavelle mean in lecture 1 today when he said that 10^-12 is actually and would be correct if it were written as 10^-7 for the concentration of H3O+?

Correct me if I misinterpreted your question; this is my best explanation for what you're asking. If Hydronium concentrations were 10^-12 (it was exactly 1.7*10^-12 I believe), than taking the negative log base ten of that produces roughly 12 (it was closer to 11.8). Because hydronium concentrations were so low, the negative log base ten of that value was so high that it was quite greater than 7, making it very basic. With a hydronium concentration of exactly 10^-7, we know that hydroxide concentration is also 10^-7 because the product of those two concentrations equal 10^-14 in 25 degrees C. We also know that -log(10^-7) is exactly 7, so that would be a neutral solution.