Can Hydroclauric Acid and Water Create a pH Greater than 7? Find Out Now!

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SUMMARY

The discussion confirms that hydrochloric acid (HCl) cannot create a solution with a pH greater than 7 under normal conditions. However, at temperatures below 25 degrees Celsius, pure water's pH can exceed 7, specifically reaching approximately 7.16 at 15 degrees Celsius. If very dilute HCl is added to cold water, it is theoretically possible for the pH to remain above 7, although the addition of HCl will still lower the pH slightly. The self-ionization of water and the endothermic nature of this process are key factors influencing these pH levels.

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I want to ask that there is any situation that the solution of Hydroclauric acid and water can make the pH of this solution gretater than 7.
 
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Yes, to some extent. At pH 7 there is no abundance of H+ or OH-.

However, water has the following reaction:

H2O -> H+ + OH-

So strickly theoretically speaking, if the acid is very diluted, your water isn't pure and the conditions are favourable, why not?
 
2H_2O \longrightarrow H_3O^+ + OH^-

The self-ionization of water is endothermic (see reaction above). If you low the temperature, the concentration of H_3O^+ will diminish and the pH will be greater than 7 for a pure water. If you add very dilute hydrochloric acid at this conditions it is very probable that the pH of this solution is greater than 7.
 
Not really. HCl, Hydrochloric Acid can only ADD H+ ions, and LOWER the pH.
If you really want to nit pick, however...
At temperatures below 25 degrees C, the pH of pure water is slightly higher than 7.0. At 15 C, it's about 7.16, for example. So if you take cold water, and any such a tiny amount of HCL that it won't lower the pH below 7.0, you can have an HCL solution with a pH above 7.00. (But adding the HCl still lowered the pH a bit).
 

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