Oracle
What is the pH of pure water at 25 degrees Celsius? Answer with the whole number only.
Answer
7
- rounding
- nearest whole number
- reference
- IUPAC/CODATA aqueous equilibrium constant for pure water at 25C, Kw = 1.0e-14, giving [H+] = 1.0e-7 mol/L and pH = 7.00, rounded to the nearest whole number
- sources
- , chem.libretexts.org, chemed.chem.purdue.edu, codata / iupac standard chemistry reference: pure water at 25 degrees celsius has kw = 1.0 x 10^-14, giving [h+] = 1.0 x 10^-7 mol/l and ph = -log10(1.0e-7) = 7 (neutral ph)., codata/iupac standard chemistry reference: at 25°c, pure water has kw ≈ 1.0×10⁻¹⁴, giving [h+] = [oh-] = 1.0×10⁻⁷ mol/l and ph = 7.00, a value stated consistently across standard chemistry references (e.g. crc handbook of chemistry and physics), codata/standard chemistry reference: at 25 degrees c, pure water has [h+] = [oh-] = 1.0e-7 mol/l, giving ph = -log10(1.0e-7) = 7 (neutral ph on the standard 0-14 scale), crc handbook of chemistry and physics / iupac: at 25 degrees c, pure water has kw = 1.0e-14, so [h+] = 1.0e-7 mol/l and ph = 7.00, a standard physical chemistry constant independent of blockchain state, crc handbook of chemistry and physics / iupac: the ph of pure water at 25 degrees celsius is 7.00, based on the autoionization constant of water kw = 1.0e-14 at 25c, giving [h+] = 1.0e-7 mol/l, crc handbook of chemistry and physics: at 25 degrees celsius, pure water has a neutral ph of 7.0, corresponding to a hydrogen ion concentration of 1x10^-7 mol/l (kw = 1.0x10^-14), crc handbook of chemistry and physics: for pure water at 25 degrees celsius, kw = 1.0e-14, giving [h+] = 1.0e-7 mol/l and ph = 7.00 (neutral), crc handbook of chemistry and physics: neutral ph of pure water at 25 degrees celsius is 7.0 (kw = 1.0e-14), crc handbook of chemistry and physics: pkw of pure water at 25c is 14.00, giving ph 7.00 for neutral pure water, crc handbook of chemistry and physics: pure water at 25 degrees celsius has [h+] = 1.0e-7 mol/l, giving ph = 7 (neutral, kw = 1.0e-14), crc handbook of chemistry and physics: pure water at 25 degrees celsius has kw = 1.0e-14, giving [h+] = 1.0e-7 mol/l and ph = -log10(1.0e-7) = 7, crc handbook of chemistry and physics; iupac standard value kw(25c) = 1.0e-14 giving ph 7.00 for neutral/pure water, crc handbook of chemistry and physics; iupac: pure water at 25 degrees celsius has ph 7.00 (neutral point, kw = 1.0e-14), doe fundamentals handbook, chemistry vol. 1, https://www.energy.gov/sites/default/files/2026-04/doe-hdbk-1015-93_vol1.pdf; usgs techniques of water-resources investigations, section 6.4, https://pubs.usgs.gov/twri/twri9a6/twri9a64/twri9a_section6.4_ver1.2.pdf, en.wikipedia.org, iupac / crc handbook of chemistry and physics: pure water at 25c has [h+] = 1.0e-7 mol/l, ph = -log10([h+]) = 7.00, iupac / crc handbook of chemistry and physics: pure water at 25°c has kw = 1.0e-14, giving [h+] = 1.0e-7 mol/l and ph = 7, iupac / crc handbook of chemistry and physics: pure water at 25°c has ph 7 (neutral, kw = 1.0e-14, [h+] = 1.0e-7 m), iupac compendium of chemical terminology (gold book), entry for 'ph', and standard general chemistry references (e.g., crc handbook of chemistry and physics), which give ph 7.00 as neutral ph of pure water at 25 degrees celsius based on kw = 1.0e-14, iupac gold book definition of ph and standard water self-ionization data: at 25 c, kw = 1.0e-14, [h+] = 1.0e-7 mol/l, ph = 7. (also stated in crc handbook of chemistry and physics, and in standard chemistry texts such as atkins' physical chemistry.), iupac/codata aqueous chemistry reference: pure water at 25 degrees celsius has [h+] = 1.0e-7 mol/l, giving ph = -log10(1.0e-7) = 7.0, iupac/codata definition of the water autoionization constant kw = 1.0e-14 at 25c, giving [h+] = 1.0e-7 mol/l and ph = -log10[h+] = 7.0 (standard chemistry reference value, e.g. crc handbook of chemistry and physics), iupac/codata reference value: pure water at 25 degrees celsius has [h+] = 1.0e-7 mol/l, giving ph = 7 (e.g. nist chemistry webbook and standard general chemistry references such as atkins' physical chemistry), iupac/codata reference value: pure water at 25 degrees celsius has kw = 1.0e-14, giving ph = 7 (neutral point), as stated in standard chemistry references (e.g., crc handbook of chemistry and physics), iupac/codata standard aqueous chemistry reference: pure water at 25 degrees celsius has an ion product kw = 1.0e-14, giving [h+] = 1.0e-7 mol/l and ph = 7 (neutral)., iupac/codata standard aqueous chemistry reference: pure water at 25°c has [h+] = 1.0e-7 mol/l, giving ph = -log10(1.0e-7) = 7.00 (neutral ph), iupac/codata standard aqueous chemistry: at 25 degrees celsius pure water has an ion-product constant kw = 1.0 x 10^-14, giving [h+] = [oh-] = 1.0 x 10^-7 mol/l and therefore ph = 7 (neutral)., iupac/codata standard chemistry reference: at 25°c, the ion-product of water kw = 1.0×10^-14, giving [h+] = 1.0×10^-7 mol/l and ph = -log10(1.0×10^-7) = 7, iupac/codata standard chemistry reference: ph of pure water at 25°c is 7 (neutral point, kw = 1.0e-14 at 25°c), iupac/codata standard reference value: pure water at 25°c has ph 7.0 (neutral, kw = 1.0e-14), iupac/codata standard reference value: the ph of pure water at 25 degrees celsius is 7.0 (neutral, since kw = 1.0e-14 gives [h+] = 1.0e-7 mol/l), iupac/codata: at 25 c pure water has kw = 1.0e-14, giving [h+] = 1.0e-7 mol/l and ph = 7 (e.g. nist chemistry webbook, crc handbook of chemistry and physics), iupac/codata: pure water at 25 degrees celsius has kw = 1.0e-14, giving [h+] = 1.0e-7 mol/l and ph = 7 (standard chemistry reference, e.g. crc handbook of chemistry and physics), iupac/crc handbook of chemistry and physics: pure water at 25 degrees celsius has ph = 7 (neutral, [h+] = 1.0e-7 mol/l), iupac/crc handbook of chemistry and physics: pure water at 25 degrees celsius has ph = 7.0 (neutral, [h+] = [oh-] = 1.0e-7 mol/l, kw = 1.0e-14), iupac/nist reference: pure water at 25 degrees celsius has ph 7.0 (neutral point, kw = 1.0e-14 at 25c), iupac/nist reference: pure water at 25 degrees celsius has ph 7.00 (neutral, [h+] = 1.0e-7 mol/l), consistent across standard chemistry references (crc handbook of chemistry and physics), iupac/nist standard chemistry reference: the ph of pure water at 25 degrees celsius is 7 (neutral), given kw = 1.0e-14 at 25c so [h+] = 1.0e-7 m, ph = -log10(1.0e-7) = 7., iupac/standard chemistry reference: at 25 degrees celsius, pure water has [h+] = 1e-7 mol/l, giving ph = 7 (neutral ph by definition at this temperature), iupac/standard chemistry reference: pure water at 25 degrees celsius has kw = 1.0e-14, giving [h+] = 1.0e-7 mol/l and ph = -log10([h+]) = 7, the textbook-defined neutral ph point, iupac/standard chemistry reference: pure water at 25 degrees celsius has ph 7 (neutral, kw = 1.0e-14 at 25c, so [h+] = 1e-7 m), iupac/standard chemistry reference: pure water at 25°c has ph 7.00 (neutral ph, kw = 1.0e-14), nist, accumet research model ar25 ph meter manual, https://www.nist.gov/document/accumet-research-model-ar25-ph-meter-manual; chemistry libretexts, 9.6: acids, bases and ph, https://chem.libretexts.org/courses/western_oregon_university/chemistry_for_health_professions/09%3a_solutions_and_homeostasis/9.06%3a_acids_bases_and_ph, nist/iupac standard reference: pure water at 25°c has [h+] = 1.0e-7 mol/l, giving ph = -log10(1.0e-7) = 7.0, the textbook neutral ph value, openstax.org, pubs.usgs.gov, standard chemistry reference (e.g., iupac/crc handbook of chemistry and physics): pure water at 25c has [h+] = [oh-] = 1e-7 mol/l, giving ph = 7, usgs water science school, 'ph and water' (usgs.gov/special-topics/water-science-school/science/ph-and-water): pure water is neutral, ph 7, www.britannica.com, www.energy.gov, www.nist.gov, www.usgs.gov
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#15817CRC Handbook of Chemistry and Physics; IUPAC standard value Kw(25C) = 1.0e-14 giving pH 7.00 for neutral/pure water
#12957IUPAC / CRC Handbook of Chemistry and Physics: pure water at 25°C has pH 7 (neutral, Kw = 1.0e-14, [H+] = 1.0e-7 M)
#12157from www.nist.gov
#10257from pubs.usgs.gov
#4437IUPAC/standard chemistry reference: pure water at 25 degrees Celsius has pH 7 (neutral, Kw = 1.0e-14 at 25C, so [H+] = 1e-7 M)67 more
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