胃酸的 pH 值是2 ，與純水比較,它所含的氫離子數量是水的多少倍？ 我算很久一直算不出來， 請大家幫我解答 ， 謝謝！?
回答 (2)
2015-12-27 5:32 pm
✔ 最佳答案
氫離子的濃度受胃液或純水的體積影響，因此比較氫離子（H^+）數目時，必須比較相同體積的胃液和純水。pH = -log[H^+]
[H^+] = 10^(-pH)
在 25°C 下，胃液的 pH = 2
[H^+] = 10^(-2) = 0.01 mol/L
在 25°C 下，純水的 pH = 7
[H^+] = 10^(-7) = 0.0000001 mol/L
在同溫下，同體積胃液含氫離子數目是純水含氫離子數目的倍數
= 0.01/0.0000001 倍
= 100000 倍
2016-01-10 10:40 am
H+(aq) concentration of gastric acid = 10^(-2) =0.01M
pH of distilled water is 7
H+(aq) concentration of distilled water = 10^(-7) = 1x10^(-7) M
H+(aq) concentration of gastric acid is 0.01/(1x10^(-7)) = 100000 times that of distilled water.
Method 2
H+(aq) concentration at pH1 is 10 times that of pH 2.
Therefore, difference= 10^(7-2) = 100000
pH of distilled water is 7
H+(aq) concentration of distilled water = 10^(-7) = 1x10^(-7) M
H+(aq) concentration of gastric acid is 0.01/(1x10^(-7)) = 100000 times that of distilled water.
Method 2
H+(aq) concentration at pH1 is 10 times that of pH 2.
Therefore, difference= 10^(7-2) = 100000
收錄日期: 2021-04-18 14:20:42
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20151226202019AAge9EH