Химическая кинетика. Наумов А.В. - 17 стр.

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ɜɚɧɧɨɣ ɜɨɞɨɣ. ɋɧɢɦɢɬɟ ɫɩɟɤɬɪ ɩɪɨɩɭɫɤɚɧɢɹ ɪɚɫɬɜɨɪɚ T(O) ɜ ɨɛɥɚɫɬɢ ɞɥɢɧ
ɜɨɥɧ 400–670 ɧɦ, ɢɫɩɨɥɶɡɭɹ ɜ ɤɚɱɟɫɬɜɟ «ɯɨɥɨɫɬɨɣ ɩɪɨɛɵ» ɤɸɜɟɬɭ ɫ ɜɨɞɨɣ.
Ɋɟɡɭɥɶɬɚɬɵ ɢɡɦɟɪɟɧɢɣ ɪɟɤɨɦɟɧɞɭɟɦ ɜɧɟɫɬɢ ɜ ɬɚɛɥɢɰɭ:
ɉɪɨɩɭɫɤɚɧɢɟ T, %
O, ɧɦ
pH = … pH = …
ȼ ɞɪɭɝɨɦ ɫɬɚɤɚɧɟ ɚɧɚɥɨɝɢɱɧɵɦ ɨɛɪɚɡɨɦ ɩɪɢɝɨɬɨɜɶɬɟ ɪɚɫɬɜɨɪ ɯɪɨɦɚɬɚ
ɤɚɥɢɹ, ɩɨɞɤɢɫɥɟɧɧɵɣ ɫɟɪɧɨɣ ɤɢɫɥɨɬɨɣ. Ⱦɥɹ ɷɬɨɝɨ ɜ ɯɨɪɨɲɨ ɩɟɪɟɦɟɲɢɜɚɟ-
ɦɵɣ ɪɚɫɬɜɨɪ ɜɧɨɫɢɬɟ ɩɢɩɟɬɤɨɣ ɤɢɫɥɨɬɭ (ɨɫɬɨɪɨɠɧɨ, ɩɨ ɤɚɩɥɹɦ!), ɧɚɛɥɸɞɚɹ
ɡɚ ɡɧɚɱɟɧɢɹɦɢ pH ɩɨ ɩɨɤɚɡɚɧɢɹɦ pH-ɦɟɬɪɚ. Ⱦɨɜɟɞɢɬɟ pH ɪɚɫɬɜɨɪɚ ɞɨ ɡɧɚ-
ɱɟɧɢɹ 1–3. Ɂɚɦɟɬɶɬɟ ɰɜɟɬ ɪɚɫɬɜɨɪɚ. ɋɧɢɦɢɬɟ ɫɩɟɤɬɪ ɩɪɨɩɭɫɤɚɧɢɹ ɜ ɨɛɥɚɫɬɢ
400–670 ɧɦ.
Ɂɚɞɚɧɢɹ. ɉɨɫɬɪɨɣɬɟ ɫɩɟɤɬɪɵ ɩɪɨɩɭɫɤɚɧɢɹ ɢɫɫɥɟɞɨɜɚɧɧɵɯ ɪɚɫɬɜɨɪɨɜ ɜ
ɤɨɨɪɞɢɧɚɬɚɯ T(O). Ⱦɥɹ ɭɞɨɛɫɬɜɚ ɫɪɚɜɧɟɧɢɹ ɨɛɚ ɫɩɟɤɬɪɚ ɪɟɤɨɦɟɧɞɭɟɦ ɩɨ-
ɫɬɪɨɢɬɶ ɧɚ ɨɞɧɨɦ ɪɢɫɭɧɤɟ. Ɉɛɴɹɫɧɢɬɟ ɪɚɡɥɢɱɢɟ ɫɩɟɤɬɪɨɜ ɫ ɬɨɱɤɢ ɡɪɟɧɢɹ
ɫɦɟɳɟɧɢɹ ɪɚɜɧɨɜɟɫɢɹ (III.1). ɋɨɝɥɚɫɭɣɬɟ ɜɚɲɟ ɧɚɛɥɸɞɟɧɢɟ ɫ ɡɚɤɨɧɨɦ ɞɟɣ-
ɫɬɜɭɸɳɢɯ ɦɚɫɫ ɢ ɩɪɢɧɰɢɩɨɦ Ʌɟ ɒɚɬɟɥɶɟ.
Ɉɛɴɹɫɧɢɬɟ ɜɢɞɢɦɵɟ ɰɜɟɬɚ ɪɚɫɬɜɨɪɨɜ ɩɨɫɥɟ ɩɨɞɤɢɫɥɟɧɢɹ ɢ ɩɨɞɳɟɥɚɱɢ-
ɜɚɧɢɹ.
2. ɂɫɫɥɟɞɨɜɚɧɢɟ ɪɚɜɧɨɜɟɫɢɹ ɞɢɫɫɨɰɢɚɰɢɢ.
Ɉɩɪɟɞɟɥɟɧɢɟ pK
a
ɫɥɚɛɨɣ ɤɢɫɥɨɬɵ
ȼ ɪɚɫɬɜɨɪɟ ɫɥɚɛɨɣ ɤɢɫɥɨɬɵ HA ɭɫɬɚɧɚɜɥɢɜɚɟɬɫɹ ɪɚɜɧɨɜɟɫɢɟ
HA
ĺ
ĸ
H
+
+ A
–
(III.2)
ɞɢɫɫɨɰɢɚɰɢɢ (ɢɨɧɢɡɚɰɢɢ). Ʉɨɧɫɬɚɧɬɚ ɷɬɨɝɨ ɪɚɜɧɨɜɟɫɢɹ K
a
ɧɚɡɵɜɚɟɬɫɹ ɤɨɧ-
ɫɬɚɧɬɨɣ ɤɢɫɥɨɬɧɨɣ ɞɢɫɫɨɰɢɚɰɢɢ ɢ ɢɦɟɟɬ ɜɢɞ:
[H ][ ]
[H ]
a
A
K
A

ɢɥɢ
[]
plg
[H ]
a
A
K
A
pH , (III.3)
ɟɫɥɢ ɩɟɪɟɣɬɢ ɤ ɥɨɝɚɪɢɮɦɭ. Ɂɞɟɫɶ ɜɜɟɞɟɧɚ ɮɭɧɤɰɢɹ pK
a
= – lg K
a
, ɧɚɡɵɜɚɟ-
ɦɚɹ ɩɨɤɚɡɚɬɟɥɟɦ ɤɨɧɫɬɚɧɬɵ.
Ɂɧɚɱɟɧɢɟ ɤɨɧɫɬɚɧɬɵ ɪɚɜɧɨɜɟɫɢɹ ɧɟ ɡɚɜɢɫɢɬ ɨɬ ɪɚɜɧɨɜɟɫɧɵɯ ɤɨɧɰɟɧɬɪɚ-
ɰɢɣ [H
+
], [A
–
], [HA] ɱɚɫɬɢɰ H
+
, A
–
ɢ HA. ɇɚɩɪɨɬɢɜ, ɤɚɤɨɜɵ ɛɵ ɧɢ ɛɵɥɢ ɷɬɢ
ɤɨɧɰɟɧɬɪɚɰɢɢ, ɢɯ ɨɬɧɨɲɟɧɢɟ ɨɫɬɚɟɬɫɹ ɩɨɫɬɨɹɧɧɵɦ ɩɪɢ ɞɚɧɧɨɣ ɬɟɦɩɟɪɚɬɭ-
ɪɟ. Ɉɬɫɸɞɚ ɹɫɧɨ, ɱɬɨ ɨɩɪɟɞɟɥɢɬɶ ɜɟɥɢɱɢɧɭ pK
a
ɦɨɠɧɨ, ɩɨɞɛɢɪɚɹ ɬɚɤɨɟ ɡɧɚ-
ɱɟɧɢɟ pH
0
, ɩɪɢ ɤɨɬɨɪɨɦ [A
–
] = [HA]. ɂɡ ɭɪɚɜɧɟɧɢɹ (III.3) ɫɥɟɞɭɟɬ, ɱɬɨ
pK
a
= pH
0
. (III.4)
Ɍɚɤɢɦ ɨɛɪɚɡɨɦ, ɡɚɞɚɱɚ ɷɤɫɩɟɪɢɦɟɧɬɚɥɶɧɨɝɨ ɨɩɪɟɞɟɥɟɧɢɹ ɤɨɧɫɬɚɧɬɵ ɞɢɫɫɨ-
33
34
ɰɢɚɰɢɢ ɫɜɨɞɢɬɫɹ ɤ ɜɵɪɚɜɧɢɜɚɧɢɸ ɤɨɧɰɟɧɬɪɚɰɢɣ ɞɢɫɫɨɰɢɢɪɨɜɚɧɧɨɣ A
–
ɢ
ɧɟɞɢɫɫɨɰɢɢɪɨɜɚɧɧɨɣ HA ɮɨɪɦ.
ɗɬɭ ɡɚɞɚɱɭ ɦɨɠɧɨ ɪɟɲɢɬɶ ɫ ɩɨɦɨɳɶɸ ɫɩɟɤɬɪɨɮɨɬɨɦɟɬɪɢɢ, ɟɫɥɢ ɮɨɪɦɵ
HA ɢ A
–
ɢɦɟɸɬ ɪɟɡɤɨ ɪɚɡɥɢɱɧɵɟ ɫɩɟɤɬɪɵ ɩɨɝɥɨɳɟɧɢɹ. Ɍɚɤɢɦ ɫɜɨɣɫɬɜɨɦ
ɨɛɥɚɞɚɸɬ ɧɟɤɨɬɨɪɵɟ ɫɥɚɛɵɟ ɨɪɝɚɧɢɱɟɫɤɢɟ ɤɢɫɥɨɬɵ. ɂɯ ɢɨɧɵ A
–
ɢ ɧɟɞɢɫɫɨ-
ɰɢɢɪɨɜɚɧɧɵɟ ɦɨɥɟɤɭɥɵ HA ɱɚɫɬɨ ɛɵɜɚɸɬ ɨɤɪɚɲɟɧɵ ɜ ɪɚɡɧɵɟ ɰɜɟɬɚ, ɬɨ
ɟɫɬɶ ɢɦɟɸɬ ɩɨɥɨɫɵ ɩɨɝɥɨɳɟɧɢɹ ɜ ɜɢɞɢɦɨɣ ɨɛɥɚɫɬɢ. ɉɨɫɤɨɥɶɤɭ ɪɚɜɧɨɜɟɫɢɟ
(III.2) ɡɚɜɢɫɢɬ ɨɬ pH, ɷɬɢ ɜɟɳɟɫɬɜɚ ɩɪɢɦɟɧɹɸɬ ɜ ɤɚɱɟɫɬɜɟ ɤɢɫɥɨɬɧɨ-
ɨɫɧóɜɧɵɯ ɢɧɞɢɤɚɬɨɪɨɜ. Ɍɚɤɨɜɵ, ɧɚɩɪɢɦɟɪ, ɮɟɧɨɥɮɬɚɥɟɢɧ, ɦɟɬɢɥɨɜɵɣ
ɨɪɚɧɠɟɜɵɣ ɢ ɦɧɨɝɢɟ ɞɪɭɝɢɟ. ȼ ɷɬɨɣ ɪɚɛɨɬɟ ɦɵ ɢɫɩɨɥɶɡɭɟɦ ɨɞɢɧ ɢɡ ɢɧɞɢ-
ɤɚɬɨɪɨɜ – ɛɪɨɦɬɢɦɨɥɨɜɵɣ ɫɢɧɢɣ, ɩɪɟɞɫɬɚɜɥɹɸɳɢɣ ɫɨɛɨɣ ɫɥɚɛɭɸ ɨɞɧɨɨɫ-
ɧóɜɧɭɸ ɤɢɫɥɨɬɭ HA.
ɐɟɥɶ ɪɚɛɨɬɵ. Ɉɩɪɟɞɟɥɢɬɶ ɤɨɧɫɬɚɧɬɭ ɞɢɫɫɨɰɢɚɰɢɢ ɤɢɫɥɨɬɧɨ-ɨɫɧɨɜɧɨɝɨ
ɢɧɞɢɤɚɬɨɪɚ ɜ ɜɨɞɧɨɦ ɪɚɫɬɜɨɪɟ.
Ɉɛɨɪɭɞɨɜɚɧɢɟ ɢ ɪɟɚɤɬɢɜɵ.
Ɏɨɬɨɦɟɬɪ ɄɎɄ-5Ɇ ɫ ɧɚɛɨɪɨɦ ɫɜɟɬɨɮɢɥɶɬɪɨɜ 400–670 ɧɦ, 4 ɤɸɜɟɬɵ ɫ ɬɨɥɳɢɧɨɣ
ɩɨɝɥɨɳɚɸɳɟɝɨ ɫɥɨɹ 10,00 ɦɦ.
pH-ɦɟɬɪ ɫɨ ɫɬɟɤɥɹɧɧɵɦ ɷɥɟɤɬɪɨɞɨɦ.
Ɇɚɝɧɢɬɧɚɹ ɦɟɲɚɥɤɚ ɫ ɹɤɨɪɟɦ.
Ɋɚɫɬɜɨɪ 0,02–0,04 ɝ/ɥ ɛɪɨɦɬɢɦɨɥɨɜɨɝɨ ɫɢɧɟɝɨ.
Ɋɚɫɬɜɨɪ ɫɟɪɧɨɣ ɤɢɫɥɨɬɵ 1 ɦɨɥɶ/ɥ.
Ɋɚɫɬɜɨɪ KOH 1 ɦɨɥɶ/ɥ.
ȼɨɞɚ ɞɢɫɬɢɥɥɢɪɨɜɚɧɧɚɹ.
4 ɫɬɚɤɚɧɚ ɟɦɤɨɫɬɶɸ 100 ɦɥ, 3 ɤɚɩɟɥɶɧɵɟ ɩɢɩɟɬɤɢ.
Ȼɭɦɚɠɧɵɟ ɮɢɥɶɬɪɵ.
ȼɵɩɨɥɧɟɧɢɟ ɪɚɛɨɬɵ. ȼ ɫɬɚɤɚɧ ɟɦɤɨɫɬɶɸ 100 ɦɥ ɜɧɟɫɢɬɟ ɨɤɨɥɨ 50 ɦɥ
ɪɚɫɬɜɨɪɚ ɛɪɨɦɬɢɦɨɥɨɜɨɝɨ ɫɢɧɟɝɨ. ɂɫɩɨɥɶɡɭɹ ɦɚɝɧɢɬɧɭɸ ɦɟɲɚɥɤɭ, ɞɨɛɟɣɬɟɫɶ
ɯɨɪɨɲɟɝɨ ɩɟɪɟɦɟɲɢɜɚɧɢɹ ɪɚɫɬɜɨɪɚ. ȼɧɟɫɢɬɟ ɜ ɪɚɫɬɜɨɪ ɷɥɟɤɬɪɨɞ pH-ɦɟɬɪɚ ɢ,
ɞɨɛɚɜɥɹɹ ɩɨ ɤɚɩɥɹɦ ɫɟɪɧɭɸ ɤɢɫɥɨɬɭ, ɞɨɜɟɞɢɬɟ pH ɞɨ ɡɧɚɱɟɧɢɹ 4–5. Ɍɚɤɢɦ
ɨɛɪɚɡɨɦ ɜɚɦɢ ɛɭɞɟɬ ɩɨɥɭɱɟɧ ɪɚɫɬɜɨɪ ʋ 1 (ɡɚɦɟɬɶɬɟ ɟɝɨ ɰɜɟɬ).
ȼ ɞɪɭɝɨɦ ɫɬɚɤɚɧɟ ɩɪɢɝɨɬɨɜɶɬɟ ɳɺɥɨɱɧɵɣ ɪɚɫɬɜɨɪ ɫ pH ɜ ɢɧɬɟɪɜɚɥɟ 9–10.
Ⱦɥɹ ɷɬɨɝɨ ɜ 50 ɦɥ ɛɪɨɦɬɢɦɨɥɨɜɨɝɨ ɫɢɧɟɝɨ ɜɧɨɫɢɬɟ ɧɟɫɤɨɥɶɤɨ ɤɚɩɟɥɶ KOH,
ɧɟɩɪɟɪɵɜɧɨ ɩɟɪɟɦɟɲɢɜɚɹ ɪɚɫɬɜɨɪ ɢ ɢɡɦɟɪɹɹ ɜɨɞɨɪɨɞɧɵɣ ɩɨɤɚɡɚɬɟɥɶ ɫ ɩɨ-
ɦɨɳɶɸ pH-ɦɟɬɪɚ. Ɍɚɤɢɦ ɨɛɪɚɡɨɦ ɛɭɞɟɬ ɩɨɥɭɱɟɧ ɪɚɫɬɜɨɪ ʋ 2 (ɡɚɦɟɬɶɬɟ ɟɝɨ
ɰɜɟɬ).
ɂɫɩɨɥɶɡɭɹ ɤɢɫɥɵɣ (ʋ 1) ɢ ɳɺɥɨɱɧɵɣ (ʋ 2) ɪɚɫɬɜɨɪɵ, ɩɪɢɝɨɬɨɜɶɬɟ ɪɹɞ
ɪɚɫɬɜɨɪɨɜ ɫɨ ɫɪɟɞɧɢɦɢ ɡɧɚɱɟɧɢɹɦɢ pH. Ⱦɥɹ ɷɬɨɝɨ ɜ ɨɬɞɟɥɶɧɨɦ ɫɬɚɤɚɧɟ
ɜɨɡɶɦɢɬɟ ɨɤɨɥɨ 30 ɦɥ ɪɚɫɬɜɨɪɚ ʋ 1. ɉɪɢɛɚɜɥɹɹ ɤ ɧɟɦɭ ɩɨ ɤɚɩɥɹɦ ɪɚɫɬɜɨɪ
ʋ 2 ɞɨɜɟɞɢɬɟ ɡɧɚɱɟɧɢɟ pH ɞɨ 6,0–6,5 (ɬɳɚɬɟɥɶɧɨ ɩɟɪɟɦɟɲɢɜɚɣɬɟ ɫ ɩɨɦɨ-
ɳɶɸ ɦɚɝɧɢɬɧɨɣ ɦɟɲɚɥɤɢ). Ʉɨɝɞɚ ɧɭɠɧɨɟ ɡɧɚɱɟɧɢɟ pH ɛɭɞɟɬ ɞɨɫɬɢɝɧɭɬɨ,
ɨɬɥɟɣɬɟ ɧɟɛɨɥɶɲɨɟ ɤɨɥɢɱɟɫɬɜɨ ɩɪɢɝɨɬɨɜɥɟɧɧɨɝɨ ɪɚɫɬɜɨɪɚ ɜ ɤɸɜɟɬɭ. Ʉɸɜɟ-
ɬɚ ɞɨɥɠɧɚ ɛɵɬɶ ɡɚɩɨɥɧɟɧɚ ɧɚ 2/3.
Ɍɚɤɢɦ ɠɟ ɦɟɬɨɞɨɦ, ɩɪɢɛɚɜɥɹɹ ɤ ɭɠɟ ɢɦɟɸɳɟɦɭɫɹ ɪɚɫɬɜɨɪɭ ɳɺɥɨɱɧɵɣ
ɜɚɧɧɨɣ ɜɨɞɨɣ. ɋɧɢɦɢɬɟ ɫɩɟɤɬɪ ɩɪɨɩɭɫɤɚɧɢɹ ɪɚɫɬɜɨɪɚ T(O) ɜ ɨɛɥɚɫɬɢ ɞɥɢɧ             ɰɢɚɰɢɢ ɫɜɨɞɢɬɫɹ ɤ ɜɵɪɚɜɧɢɜɚɧɢɸ ɤɨɧɰɟɧɬɪɚɰɢɣ ɞɢɫɫɨɰɢɢɪɨɜɚɧɧɨɣ A– ɢ
ɜɨɥɧ 400–670 ɧɦ, ɢɫɩɨɥɶɡɭɹ ɜ ɤɚɱɟɫɬɜɟ «ɯɨɥɨɫɬɨɣ ɩɪɨɛɵ» ɤɸɜɟɬɭ ɫ ɜɨɞɨɣ.            ɧɟɞɢɫɫɨɰɢɢɪɨɜɚɧɧɨɣ HA ɮɨɪɦ.
   Ɋɟɡɭɥɶɬɚɬɵ ɢɡɦɟɪɟɧɢɣ ɪɟɤɨɦɟɧɞɭɟɦ ɜɧɟɫɬɢ ɜ ɬɚɛɥɢɰɭ:                                  ɗɬɭ ɡɚɞɚɱɭ ɦɨɠɧɨ ɪɟɲɢɬɶ ɫ ɩɨɦɨɳɶɸ ɫɩɟɤɬɪɨɮɨɬɨɦɟɬɪɢɢ, ɟɫɥɢ ɮɨɪɦɵ
                                                                                  HA ɢ A– ɢɦɟɸɬ ɪɟɡɤɨ ɪɚɡɥɢɱɧɵɟ ɫɩɟɤɬɪɵ ɩɨɝɥɨɳɟɧɢɹ. Ɍɚɤɢɦ ɫɜɨɣɫɬɜɨɦ
                                 ɉɪɨɩɭɫɤɚɧɢɟ T, %                                 ɨɛɥɚɞɚɸɬ ɧɟɤɨɬɨɪɵɟ ɫɥɚɛɵɟ ɨɪɝɚɧɢɱɟɫɤɢɟ ɤɢɫɥɨɬɵ. ɂɯ ɢɨɧɵ A– ɢ ɧɟɞɢɫɫɨ-
                 O, ɧɦ
                              pH = …         pH = …                               ɰɢɢɪɨɜɚɧɧɵɟ ɦɨɥɟɤɭɥɵ HA ɱɚɫɬɨ ɛɵɜɚɸɬ ɨɤɪɚɲɟɧɵ ɜ ɪɚɡɧɵɟ ɰɜɟɬɚ, ɬɨ
                                                                                  ɟɫɬɶ ɢɦɟɸɬ ɩɨɥɨɫɵ ɩɨɝɥɨɳɟɧɢɹ ɜ ɜɢɞɢɦɨɣ ɨɛɥɚɫɬɢ. ɉɨɫɤɨɥɶɤɭ ɪɚɜɧɨɜɟɫɢɟ
                                                                                  (III.2) ɡɚɜɢɫɢɬ ɨɬ pH, ɷɬɢ ɜɟɳɟɫɬɜɚ ɩɪɢɦɟɧɹɸɬ ɜ ɤɚɱɟɫɬɜɟ ɤɢɫɥɨɬɧɨ-
                                                                                  ɨɫɧóɜɧɵɯ ɢɧɞɢɤɚɬɨɪɨɜ. Ɍɚɤɨɜɵ, ɧɚɩɪɢɦɟɪ, ɮɟɧɨɥɮɬɚɥɟɢɧ, ɦɟɬɢɥɨɜɵɣ
    ȼ ɞɪɭɝɨɦ ɫɬɚɤɚɧɟ ɚɧɚɥɨɝɢɱɧɵɦ ɨɛɪɚɡɨɦ ɩɪɢɝɨɬɨɜɶɬɟ ɪɚɫɬɜɨɪ ɯɪɨɦɚɬɚ
                                                                                  ɨɪɚɧɠɟɜɵɣ ɢ ɦɧɨɝɢɟ ɞɪɭɝɢɟ. ȼ ɷɬɨɣ ɪɚɛɨɬɟ ɦɵ ɢɫɩɨɥɶɡɭɟɦ ɨɞɢɧ ɢɡ ɢɧɞɢ-
ɤɚɥɢɹ, ɩɨɞɤɢɫɥɟɧɧɵɣ ɫɟɪɧɨɣ ɤɢɫɥɨɬɨɣ. Ⱦɥɹ ɷɬɨɝɨ ɜ ɯɨɪɨɲɨ ɩɟɪɟɦɟɲɢɜɚɟ-
                                                                                  ɤɚɬɨɪɨɜ – ɛɪɨɦɬɢɦɨɥɨɜɵɣ ɫɢɧɢɣ, ɩɪɟɞɫɬɚɜɥɹɸɳɢɣ ɫɨɛɨɣ ɫɥɚɛɭɸ ɨɞɧɨɨɫ-
ɦɵɣ ɪɚɫɬɜɨɪ ɜɧɨɫɢɬɟ ɩɢɩɟɬɤɨɣ ɤɢɫɥɨɬɭ (ɨɫɬɨɪɨɠɧɨ, ɩɨ ɤɚɩɥɹɦ!), ɧɚɛɥɸɞɚɹ
                                                                                  ɧóɜɧɭɸ ɤɢɫɥɨɬɭ HA.
ɡɚ ɡɧɚɱɟɧɢɹɦɢ pH ɩɨ ɩɨɤɚɡɚɧɢɹɦ pH-ɦɟɬɪɚ. Ⱦɨɜɟɞɢɬɟ pH ɪɚɫɬɜɨɪɚ ɞɨ ɡɧɚ-
                                                                                       ɐɟɥɶ ɪɚɛɨɬɵ. Ɉɩɪɟɞɟɥɢɬɶ ɤɨɧɫɬɚɧɬɭ ɞɢɫɫɨɰɢɚɰɢɢ ɤɢɫɥɨɬɧɨ-ɨɫɧɨɜɧɨɝɨ
ɱɟɧɢɹ 1–3. Ɂɚɦɟɬɶɬɟ ɰɜɟɬ ɪɚɫɬɜɨɪɚ. ɋɧɢɦɢɬɟ ɫɩɟɤɬɪ ɩɪɨɩɭɫɤɚɧɢɹ ɜ ɨɛɥɚɫɬɢ
                                                                                  ɢɧɞɢɤɚɬɨɪɚ ɜ ɜɨɞɧɨɦ ɪɚɫɬɜɨɪɟ.
400–670 ɧɦ.
    Ɂɚɞɚɧɢɹ. ɉɨɫɬɪɨɣɬɟ ɫɩɟɤɬɪɵ ɩɪɨɩɭɫɤɚɧɢɹ ɢɫɫɥɟɞɨɜɚɧɧɵɯ ɪɚɫɬɜɨɪɨɜ ɜ
                                                                                     Ɉɛɨɪɭɞɨɜɚɧɢɟ ɢ ɪɟɚɤɬɢɜɵ.
ɤɨɨɪɞɢɧɚɬɚɯ T(O). Ⱦɥɹ ɭɞɨɛɫɬɜɚ ɫɪɚɜɧɟɧɢɹ ɨɛɚ ɫɩɟɤɬɪɚ ɪɟɤɨɦɟɧɞɭɟɦ ɩɨ-                  Ɏɨɬɨɦɟɬɪ ɄɎɄ-5Ɇ ɫ ɧɚɛɨɪɨɦ ɫɜɟɬɨɮɢɥɶɬɪɨɜ 400–670 ɧɦ, 4 ɤɸɜɟɬɵ ɫ ɬɨɥɳɢɧɨɣ
ɫɬɪɨɢɬɶ ɧɚ ɨɞɧɨɦ ɪɢɫɭɧɤɟ. Ɉɛɴɹɫɧɢɬɟ ɪɚɡɥɢɱɢɟ ɫɩɟɤɬɪɨɜ ɫ ɬɨɱɤɢ ɡɪɟɧɢɹ              ɩɨɝɥɨɳɚɸɳɟɝɨ ɫɥɨɹ 10,00 ɦɦ.
ɫɦɟɳɟɧɢɹ ɪɚɜɧɨɜɟɫɢɹ (III.1). ɋɨɝɥɚɫɭɣɬɟ ɜɚɲɟ ɧɚɛɥɸɞɟɧɢɟ ɫ ɡɚɤɨɧɨɦ ɞɟɣ-                pH-ɦɟɬɪ ɫɨ ɫɬɟɤɥɹɧɧɵɦ ɷɥɟɤɬɪɨɞɨɦ.
ɫɬɜɭɸɳɢɯ ɦɚɫɫ ɢ ɩɪɢɧɰɢɩɨɦ Ʌɟ ɒɚɬɟɥɶɟ.                                                 Ɇɚɝɧɢɬɧɚɹ ɦɟɲɚɥɤɚ ɫ ɹɤɨɪɟɦ.
    Ɉɛɴɹɫɧɢɬɟ ɜɢɞɢɦɵɟ ɰɜɟɬɚ ɪɚɫɬɜɨɪɨɜ ɩɨɫɥɟ ɩɨɞɤɢɫɥɟɧɢɹ ɢ ɩɨɞɳɟɥɚɱɢ-                  Ɋɚɫɬɜɨɪ 0,02–0,04 ɝ/ɥ ɛɪɨɦɬɢɦɨɥɨɜɨɝɨ ɫɢɧɟɝɨ.
ɜɚɧɢɹ.                                                                                Ɋɚɫɬɜɨɪ ɫɟɪɧɨɣ ɤɢɫɥɨɬɵ 1 ɦɨɥɶ/ɥ.
                                                                                      Ɋɚɫɬɜɨɪ KOH 1 ɦɨɥɶ/ɥ.
                                                                                      ȼɨɞɚ ɞɢɫɬɢɥɥɢɪɨɜɚɧɧɚɹ.
              2. ɂɫɫɥɟɞɨɜɚɧɢɟ ɪɚɜɧɨɜɟɫɢɹ ɞɢɫɫɨɰɢɚɰɢɢ.                                 4 ɫɬɚɤɚɧɚ ɟɦɤɨɫɬɶɸ 100 ɦɥ, 3 ɤɚɩɟɥɶɧɵɟ ɩɢɩɟɬɤɢ.
                  Ɉɩɪɟɞɟɥɟɧɢɟ pKa ɫɥɚɛɨɣ ɤɢɫɥɨɬɵ                                      Ȼɭɦɚɠɧɵɟ ɮɢɥɶɬɪɵ.

   ȼ ɪɚɫɬɜɨɪɟ ɫɥɚɛɨɣ ɤɢɫɥɨɬɵ HA ɭɫɬɚɧɚɜɥɢɜɚɟɬɫɹ ɪɚɜɧɨɜɟɫɢɟ                            ȼɵɩɨɥɧɟɧɢɟ ɪɚɛɨɬɵ. ȼ ɫɬɚɤɚɧ ɟɦɤɨɫɬɶɸ 100 ɦɥ ɜɧɟɫɢɬɟ ɨɤɨɥɨ 50 ɦɥ
                                                                                  ɪɚɫɬɜɨɪɚ ɛɪɨɦɬɢɦɨɥɨɜɨɝɨ ɫɢɧɟɝɨ. ɂɫɩɨɥɶɡɭɹ ɦɚɝɧɢɬɧɭɸ ɦɟɲɚɥɤɭ, ɞɨɛɟɣɬɟɫɶ
                              HA ĺ    +
                                  ĸH +A
                                           –
                                                                (III.2)
                                                                                  ɯɨɪɨɲɟɝɨ ɩɟɪɟɦɟɲɢɜɚɧɢɹ ɪɚɫɬɜɨɪɚ. ȼɧɟɫɢɬɟ ɜ ɪɚɫɬɜɨɪ ɷɥɟɤɬɪɨɞ pH-ɦɟɬɪɚ ɢ,
ɞɢɫɫɨɰɢɚɰɢɢ (ɢɨɧɢɡɚɰɢɢ). Ʉɨɧɫɬɚɧɬɚ ɷɬɨɝɨ ɪɚɜɧɨɜɟɫɢɹ Ka ɧɚɡɵɜɚɟɬɫɹ ɤɨɧ-            ɞɨɛɚɜɥɹɹ ɩɨ ɤɚɩɥɹɦ ɫɟɪɧɭɸ ɤɢɫɥɨɬɭ, ɞɨɜɟɞɢɬɟ pH ɞɨ ɡɧɚɱɟɧɢɹ 4–5. Ɍɚɤɢɦ
ɫɬɚɧɬɨɣ ɤɢɫɥɨɬɧɨɣ ɞɢɫɫɨɰɢɚɰɢɢ ɢ ɢɦɟɟɬ ɜɢɞ:                                        ɨɛɪɚɡɨɦ ɜɚɦɢ ɛɭɞɟɬ ɩɨɥɭɱɟɧ ɪɚɫɬɜɨɪ ʋ 1 (ɡɚɦɟɬɶɬɟ ɟɝɨ ɰɜɟɬ).
                     [H  ][ A ]                       [ A ]                        ȼ ɞɪɭɝɨɦ ɫɬɚɤɚɧɟ ɩɪɢɝɨɬɨɜɶɬɟ ɳɺɥɨɱɧɵɣ ɪɚɫɬɜɨɪ ɫ pH ɜ ɢɧɬɟɪɜɚɥɟ 9–10.
               Ka                   ɢɥɢ   pK a    lg           pH ,   (III.3)
                                                                                  Ⱦɥɹ ɷɬɨɝɨ ɜ 50 ɦɥ ɛɪɨɦɬɢɦɨɥɨɜɨɝɨ ɫɢɧɟɝɨ ɜɧɨɫɢɬɟ ɧɟɫɤɨɥɶɤɨ ɤɚɩɟɥɶ KOH,
                       [HA]                             [HA]
                                                                                  ɧɟɩɪɟɪɵɜɧɨ ɩɟɪɟɦɟɲɢɜɚɹ ɪɚɫɬɜɨɪ ɢ ɢɡɦɟɪɹɹ ɜɨɞɨɪɨɞɧɵɣ ɩɨɤɚɡɚɬɟɥɶ ɫ ɩɨ-
ɟɫɥɢ ɩɟɪɟɣɬɢ ɤ ɥɨɝɚɪɢɮɦɭ. Ɂɞɟɫɶ ɜɜɟɞɟɧɚ ɮɭɧɤɰɢɹ pKa = – lg Ka, ɧɚɡɵɜɚɟ-
                                                                                  ɦɨɳɶɸ pH-ɦɟɬɪɚ. Ɍɚɤɢɦ ɨɛɪɚɡɨɦ ɛɭɞɟɬ ɩɨɥɭɱɟɧ ɪɚɫɬɜɨɪ ʋ 2 (ɡɚɦɟɬɶɬɟ ɟɝɨ
ɦɚɹ ɩɨɤɚɡɚɬɟɥɟɦ ɤɨɧɫɬɚɧɬɵ.
                                                                                  ɰɜɟɬ).
    Ɂɧɚɱɟɧɢɟ ɤɨɧɫɬɚɧɬɵ ɪɚɜɧɨɜɟɫɢɹ ɧɟ ɡɚɜɢɫɢɬ ɨɬ ɪɚɜɧɨɜɟɫɧɵɯ ɤɨɧɰɟɧɬɪɚ-
                                                                                      ɂɫɩɨɥɶɡɭɹ ɤɢɫɥɵɣ (ʋ 1) ɢ ɳɺɥɨɱɧɵɣ (ʋ 2) ɪɚɫɬɜɨɪɵ, ɩɪɢɝɨɬɨɜɶɬɟ ɪɹɞ
ɰɢɣ [H+], [A–], [HA] ɱɚɫɬɢɰ H+, A– ɢ HA. ɇɚɩɪɨɬɢɜ, ɤɚɤɨɜɵ ɛɵ ɧɢ ɛɵɥɢ ɷɬɢ
                                                                                  ɪɚɫɬɜɨɪɨɜ ɫɨ ɫɪɟɞɧɢɦɢ ɡɧɚɱɟɧɢɹɦɢ pH. Ⱦɥɹ ɷɬɨɝɨ ɜ ɨɬɞɟɥɶɧɨɦ ɫɬɚɤɚɧɟ
ɤɨɧɰɟɧɬɪɚɰɢɢ, ɢɯ ɨɬɧɨɲɟɧɢɟ ɨɫɬɚɟɬɫɹ ɩɨɫɬɨɹɧɧɵɦ ɩɪɢ ɞɚɧɧɨɣ ɬɟɦɩɟɪɚɬɭ-
                                                                                  ɜɨɡɶɦɢɬɟ ɨɤɨɥɨ 30 ɦɥ ɪɚɫɬɜɨɪɚ ʋ 1. ɉɪɢɛɚɜɥɹɹ ɤ ɧɟɦɭ ɩɨ ɤɚɩɥɹɦ ɪɚɫɬɜɨɪ
ɪɟ. Ɉɬɫɸɞɚ ɹɫɧɨ, ɱɬɨ ɨɩɪɟɞɟɥɢɬɶ ɜɟɥɢɱɢɧɭ pKa ɦɨɠɧɨ, ɩɨɞɛɢɪɚɹ ɬɚɤɨɟ ɡɧɚ-
                                                                                  ʋ 2 ɞɨɜɟɞɢɬɟ ɡɧɚɱɟɧɢɟ pH ɞɨ 6,0–6,5 (ɬɳɚɬɟɥɶɧɨ ɩɟɪɟɦɟɲɢɜɚɣɬɟ ɫ ɩɨɦɨ-
ɱɟɧɢɟ pH0, ɩɪɢ ɤɨɬɨɪɨɦ [A–] = [HA]. ɂɡ ɭɪɚɜɧɟɧɢɹ (III.3) ɫɥɟɞɭɟɬ, ɱɬɨ
                                                                                  ɳɶɸ ɦɚɝɧɢɬɧɨɣ ɦɟɲɚɥɤɢ). Ʉɨɝɞɚ ɧɭɠɧɨɟ ɡɧɚɱɟɧɢɟ pH ɛɭɞɟɬ ɞɨɫɬɢɝɧɭɬɨ,
                                    pKa = pH0.                          (III.4)   ɨɬɥɟɣɬɟ ɧɟɛɨɥɶɲɨɟ ɤɨɥɢɱɟɫɬɜɨ ɩɪɢɝɨɬɨɜɥɟɧɧɨɝɨ ɪɚɫɬɜɨɪɚ ɜ ɤɸɜɟɬɭ. Ʉɸɜɟ-
                                                                                  ɬɚ ɞɨɥɠɧɚ ɛɵɬɶ ɡɚɩɨɥɧɟɧɚ ɧɚ 2/3.
Ɍɚɤɢɦ ɨɛɪɚɡɨɦ, ɡɚɞɚɱɚ ɷɤɫɩɟɪɢɦɟɧɬɚɥɶɧɨɝɨ ɨɩɪɟɞɟɥɟɧɢɹ ɤɨɧɫɬɚɧɬɵ ɞɢɫɫɨ-                 Ɍɚɤɢɦ ɠɟ ɦɟɬɨɞɨɦ, ɩɪɢɛɚɜɥɹɹ ɤ ɭɠɟ ɢɦɟɸɳɟɦɭɫɹ ɪɚɫɬɜɨɪɭ ɳɺɥɨɱɧɵɣ
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