Химическая кинетика. Наумов А.В. - 18 стр.

UptoLike

ВУЗ: 

ВГУ | Воронеж

Составители: 

Рубрика: 

35
ʋ 2, ɩɪɢɝɨɬɨɜɶɬɟ ɪɚɫɬɜɨɪɵ ɫ pH = 6,5–7,0 ɢ 7,0–7,5. Ɂɞɟɫɶ ɭɤɚɡɚɧɵ ɬɨɥɶɤɨ ɢɧ-
ɬɟɪɜɚɥɵ, ɜ ɤɨɬɨɪɵɯ ɞɨɥɠɟɧ ɥɟɠɚɬɶ ɜɨɞɨɪɨɞɧɵɣ ɩɨɤɚɡɚɬɟɥɶ. ɇɟɨɛɯɨɞɢɦɨ ɢɡɦɟ-
ɪɢɬɶ ɢ ɡɚɩɢɫɚɬɶ ɡɧɚɱɟɧɢɹ pH ɤɚɠɞɨɝɨ ɪɚɫɬɜɨɪɚ ɫ ɬɨɱɧɨɫɬɶɸ ɞɨ ɜɬɨɪɨɝɨ ɡɧɚɤɚ.
ɉɨ ɬɪɟɛɨɜɚɧɢɸ ɩɪɟɩɨɞɚɜɚɬɟɥɹ ɱɢɫɥɨ ɩɪɨɛ ɦɨɠɟɬ ɛɵɬɶ ɭɜɟɥɢɱɟɧɨ ɞɨ 5. Ɇɨɠɧɨ ɢɡ-
ɦɟɧɹɬɶ pH ɢɫɫɥɟɞɭɟɦɵɯ ɪɚɫɬɜɨɪɨɜ ɜ ɩɪɟɞɟɥɚɯ ɨɬ 6,0 ɞɨ 7,5.
ɂɡɦɟɪɶɬɟ ɨɩɬɢɱɟɫɤɭɸ ɩɥɨɬɧɨɫɬɶ ɬɪɟɯ ɪɚɫɬɜɨɪɨɜ ɫɨ ɫɪɟɞɧɢɦɢ ɡɧɚɱɟɧɢɹɦɢ
pH, ɢɫɩɨɥɶɡɭɹ ɜ ɤɚɱɟɫɬɜɟ «ɯɨɥɨɫɬɨɣ ɩɪɨɛɵ» ɤɸɜɟɬɭ ɫ ɞɢɫɬɢɥɥɢɪɨɜɚɧɧɨɣ ɜɨ-
ɞɨɣ. ɂɡɦɟɪɟɧɢɹ ɩɪɨɜɟɞɢɬɟ ɧɚ ɞɜɭɯ ɞɥɢɧɚɯ ɜɨɥɧ ɫɨ ɫɜɟɬɨɮɢɥɶɬɪɚɦɢ 440 ɢ
590 ɧɦ. Ɋɟɡɭɥɶɬɚɬɵ ɦɨɠɧɨ ɡɚɧɟɫɬɢ ɜ ɩɟɪɜɵɟ ɬɪɢ ɤɨɥɨɧɤɢ ɬɚɛɥɢɰɵ:
Ɉɩɬɢɱɟɫɤɚɹ ɩɥɨɬɧɨɫɬɶ D Ɋɚɜɧɨɜɟɫɧ. ɤɨɧɰ-ɹ, ɝ/ɥ
pH
440 ɧɦ 590 ɧɦ HAA
–
pK
a
Ɉɛɪɚɛɨɬɤɚ ɪɟɡɭɥɶɬɚɬɨɜ.
ɋɨɝɥɚɫɧɨ ɩɪɢɧɰɢɩɭ Ʌɟ ɒɚɬɟɥɶɟ ɜ ɳɺɥɨɱɧɨɦ
ɪɚɫɬɜɨɪɟ (ɩɪɢ pH > 9) ɞɨɦɢɧɢɪɭɟɬ ɞɢɫɫɨɰɢɢɪɨɜɚɧɧɚɹ ɮɨɪɦɚ A
–
ɛɪɨɦɬɢɦɨ-
ɥɨɜɨɝɨ ɫɢɧɟɝɨ. Ʉɨɧɰɟɧɬɪɚɰɢɟɣ ɧɟɞɢɫɫɨɰɢɢɪɨɜɚɧɧɵɯ ɦɨɥɟɤɭɥ HA ɦɨɠɧɨ
ɩɪɟɧɟɛɪɟɱɶ. ɂɨɧɵ A
–
ɢɦɟɸɬ ɩɨɥɨɫɭ ɩɨɝɥɨɳɟɧɢɹ ɜ ɤɪɚɫɧɨɣ ɨɛɥɚɫɬɢ (ɫɦ.
ɪɢɫ. 6) ɢɨɤɪɚɲɟɧɵɜ ɫɢɧɢɣ ɰɜɟɬ. ȼ ɤɢɫɥɨɦ ɪɚɫɬɜɨɪɟ (ɩɪɢ pH < 5), ɧɚ-
ɨɛɨɪɨɬ, ɩɪɢɫɭɬɫɬɜɭɸɬ ɦɨɥɟɤɭɥɵ HA, ɚ ɤɨɧɰɟɧɬɪɚɰɢɹ ɢɨɧɨɜ A
–
ɱɪɟɡɜɵɱɚɣɧɨ
ɦɚɥɚ. Ɉɤɚɡɵɜɚɟɬɫɹ, ɱɬɨ ɩɪɢ ɩɪɢɫɨɟɞɢɧɟɧɢɢ ɩɪɨɬɨɧɚ (A
–
+ H
+
ĺ HA) ɫɩɟɤɬɪ
ɜɟɳɟɫɬɜɚ ɫɢɥɶɧɨ ɢɡɦɟɧɹɟɬɫɹ: ɢɫɱɟɡɚɟɬ ɤɪɚɫɧɚɹ ɩɨɥɨɫɚ ɩɨɝɥɨɳɟɧɢɹ ɢ ɩɨɹɜ-
ɥɹɟɬɫɹ ɫɢɧɹɹ. Ɍɚɤɢɦ ɨɛɪɚɡɨɦ, ɤɢɫɥɚɹ ɮɨɪɦɚ ɨɤɪɚɲɟɧɚ ɜ ɨ ɪ ɚ ɧ ɠ ɟ ɜ ɨ-
ɤɪɚɫɧɵɣ ɰɜɟɬ.
ɉɪɢ ɫɪɟɞɧɢɯ ɡɧɚɱɟɧɢɹɯ pH ɜ ɪɚɜɧɨɜɟɫɢɢ (III.4) ɩɪɢɫɭɬɫɬɜɭɸɬ ɨɛɟ ɮɨɪ-
ɦɵ – HA ɢ A
–
. ɂɡɦɟɪɹɹ ɨɩɬɢɱɟɫɤɭɸ ɩɥɨɬɧɨɫɬɶ ɧɚ ɞɥɢɧɟ ɜɨɥɧɵ 440, ɦɵ ɨɛ-
ɧɚɪɭɠɢɜɚɟɦ ɩɟɪɜɭɸ ɢɡ ɷɬɢɯ ɮɨɪɦ; ɧɚ ɞɥɢɧɟ ɜɨɥɧɵ 590 ɧɦ – ɜɬɨɪɭɸ. ɉɨ
ɡɚɤɨɧɭ Ȼɟɪɚ (II.5)
D
440
= E
440
[HA], D
590
= E
590
[A
–
]. (III.5)
Ɉɬɫɸɞɚ ɦɨɠɧɨ ɨɩɪɟɞɟɥɢɬɶ ɪɚɜɧɨɜɟɫɧɵɟ ɤɨɧɰɟɧɬɪɚɰɢɢ. ɉɪɟɞɜɚɪɢɬɟɥɶɧɵɟ
(ɝɪɚɞɭɢɪɨɜɨɱɧɵɟ) ɢɡɦɟɪɟɧɢɹ ɩɨɤɚɡɵɜɚɸɬ, ɱɬɨ
E
440
= 20,46 ɥ/ɝ, E
590
= 41,74 ɥ/ɝ.
Ɉɩɪɟɞɟɥɟɧɢɟ ɤɨɧɫɬɚɧɬɵ pK
a
(ɩɟɪɜɵɣ ɫɩɨɫɨɛ). ɉɨ ɮɨɪɦɭɥɚɦ (III.5) ɜɵ-
ɱɢɫɥɢɬɟ ɪɚɜɧɨɜɟɫɧɵɟ ɤɨɧɰɟɧɬɪɚɰɢɢ [HA] ɢ [A
–
] ɞɥɹ ɤɚɠɞɨɝɨ ɢɡ ɢɫɫɥɟɞɨ-
ɜɚɧɧɵɯ ɡɧɚɱɟɧɢɣ pH. Ɋɟɡɭɥɶɬɚɬɵ ɡɚɧɟɫɢɬɟ ɜ ɬɚɛɥɢɰɭ. ɉɨ ɭɪɚɜɧɟɧɢɸ (III.3)
ɜɵɱɢɫɥɢɬɟ ɷɤɫɩɟɪɢɦɟɧɬɚɥɶɧɵɟ ɡɧɚɱɟɧɢɹ pK
a
, ɧɚɣɞɢɬɟ ɫɪɟɞɧɟɟ ɡɧɚɱɟɧɢɟ,
ɚɛɫɨɥɸɬɧɭɸ ɢ ɨɬɧɨɫɢɬɟɥɶɧɭɸ ɩɨɝɪɟɲɧɨɫɬɢ.
ȼɬɨɪɨɣ ɫɩɨɫɨɛ. ɉɨɫɬɪɨɣɬɟ ɝɪɚɮɢɤɢ ɡɚɜɢɫɢɦɨɫɬɟɣ ɪɚɜɧɨɜɟɫɧɵɯ ɤɨɧɰɟɧ-
ɬɪɚɰɢɣ [HA] ɢ [A
–
] ɨɬ pH ɜ ɨɞɧɨɣ ɤɨɨɪɞɢɧɚɬɧɨɣ ɫɟɬɤɟ. ɗɤɫɩɟɪɢɦɟɧɬɚɥɶɧɵɟ
36
ɬɨɱɤɢ ɫɨɟɞɢɧɢɬɟ ɩɥɚɜɧɵɦɢ ɤɪɢɜɵɦɢ, ɩɪɨɞɨɥɠɚɹ ɢɯ ɞɨ ɜɡɚɢɦɧɨɝɨ ɩɟɪɟɫɟ-
ɱɟɧɢɹ. Ɍɨɱɤɚ ɩɟɪɟɫɟɱɟɧɢɹ pH
0
, ɬɨ ɟɫɬɶ ɬɨɱɤɚ ɪɚɜɟɧɫɬɜɚ ɤɨɧɰɟɧɬɪɚɰɢɣ
[HA] = [A
–
], ɫɨɨɬɜɟɬɫɬɜɭɟɬ ɜɟɥɢɱɢɧɟ pK
a
.
3. ɂɫɫɥɟɞɨɜɚɧɢɟ ɤɢɧɟɬɢɤɢ ɪɟɚɤɰɢɢ ɪɚɡɥɨɠɟɧɢɹ
ɬɢɨɫɟɪɧɨɣ ɤɢɫɥɨɬɵ
Ɍɢɨɫɟɪɧɚɹ ɤɢɫɥɨɬɚ H
2
S
2
O
3
ɜ ɜɨɞɧɵɯ ɪɚɫɬɜɨɪɚɯ ɧɟɭɫɬɨɣɱɢɜɚ ɢ ɪɚɡɥɚɝɚ-
ɟɬɫɹ ɫɨɝɥɚɫɧɨ ɭɪɚɜɧɟɧɢɸ
H
2
S
2
O
3
(ɪ.)
ĺ SO
2
(ɪ.)
+ H
2
O + S
(ɬɜ.)
. (III.6)
ȼ ɪɟɡɭɥɶɬɚɬɟ ɪɟɚɤɰɢɢ ɜɵɞɟɥɹɟɬɫɹ ɨɤɫɢɞ ɫɟɪɵ SO
2
, ɤɨɬɨɪɵɣ ɨɫɬɚɟɬɫɹ ɜ ɪɚɫ-
ɬɜɨɪɟ (ɪ.), ɢ ɧɟɪɚɫɬɜɨɪɢɦɚɹ ɜ ɜɨɞɟ ɫɟɪɚ. ɉɨɫɥɟɞɧɹɹ ɜɵɞɟɥɹɟɬɫɹ ɜ ɜɢɞɟ ɨɱɟɧɶ
ɦɟɥɤɢɯ ɬɜɟɪɞɵɯ ɱɚɫɬɢɰ, ɨɛɪɚɡɭɸɳɢɯ ɤɨɥɥɨɢɞɧɵɣ ɪɚɫɬɜɨɪ (ɡɨɥɶ).
Ʉɨɥɥɨɢɞɧɵɟ ɱɚɫɬɢɰɵ ɪɚɫɫɟɢɜɚɸɬ ɫɜɟɬ. ȼ ɪɟɡɭɥɶɬɚɬɟ ɨɩɬɢɱɟɫɤɚɹ ɩɥɨɬ-
ɧɨɫɬɶ ɤɨɥɥɨɢɞɧɨɝɨ ɪɚɫɬɜɨɪɚ ɩɨɧɢɠɚɟɬɫɹ, ɞɚɠɟ ɟɫɥɢ ɜɟɳɟɫɬɜɨ ɧɟ ɢɦɟɟɬ
ɫɨɛɫɬɜɟɧɧɨɣ ɨɤɪɚɫɤɢ. ȼ ɩɟɪɜɨɦ ɩɪɢɛɥɢɠɟɧɢɢ ɦɨɠɧɨ ɫɱɢɬɚɬɶ, ɱɬɨ ɨɩɬɢɱɟ-
ɫɤɚɹ ɩɥɨɬɧɨɫɬɶ ɩɪɨɩɨɪɰɢɨɧɚɥɶɧɚ ɱɢɫɥɭ ɪɚɫɫɟɢɜɚɸɳɢɯ n ɱɚɫɬɢɰ ɜ ɟɞɢɧɢɰɟ
ɨɛɴɟɦɚ: D
n. ɗɬɢɦ ɦɨɠɧɨ ɜɨɫɩɨɥɶɡɨɜɚɬɶɫɹ ɞɥɹ ɢɫɫɥɟɞɨɜɚɧɢɹ ɤɢɧɟɬɢɤɢ
ɪɟɚɤɰɢɢ (III.6), ɩɨɫɤɨɥɶɤɭ ɡɚɜɢɫɢɦɨɫɬɶ ɨɬ ɜɪɟɦɟɧɢ D(W) ɩɨɤɚɡɵɜɚɟɬ ɤɢɧɟ-
ɬɢɤɭ ɧɚɤɨɩɥɟɧɢɹ ɨɞɧɨɝɨ ɢɡ ɩɪɨɞɭɤɬɨɜ ɪɟɚɤɰɢɢ. Ⱦɪɭɝɢɟ ɜɟɳɟɫɬɜɚ, ɭɱɚɫɬ-
ɜɭɸɳɢɟ ɜ ɪɟɚɤɰɢɢ, ɧɟ ɩɨɝɥɨɳɚɸɬ ɢ ɧɟ ɪɚɫɫɟɢɜɚɸɬ ɫɜɟɬ ɜ ɜɢɞɢɦɨɣ ɨɛɥɚɫɬɢ.
ɐɟɥɶ ɪɚɛɨɬɵ. ɂɫɫɥɟɞɨɜɚɬɶ ɡɚɜɢɫɢɦɨɫɬɶ ɫɤɨɪɨɫɬɢ ɪɟɚɤɰɢɢ ɨɬ ɤɨɧɰɟɧ-
ɬɪɚɰɢɢ ɩɪɟɜɪɚɳɚɸɳɟɝɨɫɹ ɜɟɳɟɫɬɜɚ. Ɉɩɪɟɞɟɥɢɬɶ ɷɧɟɪɝɢɸ ɚɤɬɢɜɚɰɢɢ ɪɟɚɤ-
ɰɢɢ ɪɚɡɥɨɠɟɧɢɹ ɬɢɨɫɟɪɧɨɣ ɤɢɫɥɨɬɵ.
Ɉɛɨɪɭɞɨɜɚɧɢɟ ɢ ɪɟɚɤɬɢɜɵ.
Ɏɨɬɨɦɟɬɪ ɄɎɄ-5Ɇ ɫɨ ɫɜɟɬɨɮɢɥɶɬɪɨɦ 400 ɧɦ, 4 ɩɪɨɛɢɪɤɢ ɞɥɹ ɮɨɬɨɦɟɬɪɢɪɨɜɚɧɢɹ
(ɢɡ ɤɨɦɩɥɟɤɬɚ ɩɪɢɛɨɪɚ).
ɋɟɤɭɧɞɨɦɟɪ.
Ɍɟɪɦɨɦɟɬɪ ɥɚɛɨɪɚɬɨɪɧɵɣ.
Ɋɚɫɬɜɨɪ ɬɢɨɫɭɥɶɮɚɬɚ ɧɚɬɪɢɹ 0,1 ɦɨɥɶ/ɥ.
Ɋɚɫɬɜɨɪ ɫɟɪɧɨɣ ɤɢɫɥɨɬɵ 0,1 ɦɨɥɶ/ɥ.
ȼɨɞɚ ɞɢɫɬɢɥɥɢɪɨɜɚɧɧɚɹ.
4 ɫɬɚɤɚɧɚ ɟɦɤɨɫɬɶɸ 100 ɦɥ, 3 ɦɟɪɧɵɯ ɰɢɥɢɧɞɪɚ ɧɚ 50 ɦɥ.
2 ɛɨɥɶɲɢɟ ɩɪɨɛɢɪɤɢ.
Ɍɟɪɦɨɫɬɚɬ ɢɥɢ ɜɨɞɹɧɚɹ ɛɚɧɹ.
Ȼɭɦɚɠɧɵɟ ɮɢɥɶɬɪɵ.
ȼɵɩɨɥɧɟɧɢɟ ɪɚɛɨɬɵ.
1. ɉɨɞɝɨɬɨɜɶɬɟ ɮɨɬɨɦɟɬɪ ɤ ɢɡɦɟɪɟɧɢɹɦ ɨɩɬɢɱɟ-
ɫɤɨɣ ɩɥɨɬɧɨɫɬɢ. ɍɫɬɚɧɨɜɢɬɟ ɫɜɟɬɨɮɢɥɶɬɪ ɧɚ 400 ɧɦ. ȼ ɩɪɨɛɢɪɤɟ ɞɥɹ ɮɨɬɨ-
ɦɟɬɪɢɪɨɜɚɧɢɹ (ɧɚɯɨɞɢɬɫɹ ɜ ɤɨɦɩɥɟɤɬɟ ɩɪɢɛɨɪɚ) ɜ ɤɚɱɟɫɬɜɟ «ɯɨɥɨɫɬɨɣ ɩɪɨ-
ɛɵ» ɢɡɦɟɪɶɬɟ ɞɢɫɬɢɥɥɢɪɨɜɚɧɧɭɸ ɜɨɞɭ.
ʋ 2, ɩɪɢɝɨɬɨɜɶɬɟ ɪɚɫɬɜɨɪɵ ɫ pH = 6,5–7,0 ɢ 7,0–7,5. Ɂɞɟɫɶ ɭɤɚɡɚɧɵ ɬɨɥɶɤɨ ɢɧ-     ɬɨɱɤɢ ɫɨɟɞɢɧɢɬɟ ɩɥɚɜɧɵɦɢ ɤɪɢɜɵɦɢ, ɩɪɨɞɨɥɠɚɹ ɢɯ ɞɨ ɜɡɚɢɦɧɨɝɨ ɩɟɪɟɫɟ-
ɬɟɪɜɚɥɵ, ɜ ɤɨɬɨɪɵɯ ɞɨɥɠɟɧ ɥɟɠɚɬɶ ɜɨɞɨɪɨɞɧɵɣ ɩɨɤɚɡɚɬɟɥɶ. ɇɟɨɛɯɨɞɢɦɨ ɢɡɦɟ-         ɱɟɧɢɹ. Ɍɨɱɤɚ ɩɟɪɟɫɟɱɟɧɢɹ pH0, ɬɨ ɟɫɬɶ ɬɨɱɤɚ ɪɚɜɟɧɫɬɜɚ ɤɨɧɰɟɧɬɪɚɰɢɣ
ɪɢɬɶ ɢ ɡɚɩɢɫɚɬɶ ɡɧɚɱɟɧɢɹ pH ɤɚɠɞɨɝɨ ɪɚɫɬɜɨɪɚ ɫ ɬɨɱɧɨɫɬɶɸ ɞɨ ɜɬɨɪɨɝɨ ɡɧɚɤɚ.       [HA] = [A–], ɫɨɨɬɜɟɬɫɬɜɭɟɬ ɜɟɥɢɱɢɧɟ pKa.
   ɉɨ ɬɪɟɛɨɜɚɧɢɸ ɩɪɟɩɨɞɚɜɚɬɟɥɹ ɱɢɫɥɨ ɩɪɨɛ ɦɨɠɟɬ ɛɵɬɶ ɭɜɟɥɢɱɟɧɨ ɞɨ 5. Ɇɨɠɧɨ ɢɡ-
ɦɟɧɹɬɶ pH ɢɫɫɥɟɞɭɟɦɵɯ ɪɚɫɬɜɨɪɨɜ ɜ ɩɪɟɞɟɥɚɯ ɨɬ 6,0 ɞɨ 7,5.
                                                                                             3. ɂɫɫɥɟɞɨɜɚɧɢɟ ɤɢɧɟɬɢɤɢ ɪɟɚɤɰɢɢ ɪɚɡɥɨɠɟɧɢɹ
   ɂɡɦɟɪɶɬɟ ɨɩɬɢɱɟɫɤɭɸ ɩɥɨɬɧɨɫɬɶ ɬɪɟɯ ɪɚɫɬɜɨɪɨɜ ɫɨ ɫɪɟɞɧɢɦɢ ɡɧɚɱɟɧɢɹɦɢ                                    ɬɢɨɫɟɪɧɨɣ ɤɢɫɥɨɬɵ
pH, ɢɫɩɨɥɶɡɭɹ ɜ ɤɚɱɟɫɬɜɟ «ɯɨɥɨɫɬɨɣ ɩɪɨɛɵ» ɤɸɜɟɬɭ ɫ ɞɢɫɬɢɥɥɢɪɨɜɚɧɧɨɣ ɜɨ-
ɞɨɣ. ɂɡɦɟɪɟɧɢɹ ɩɪɨɜɟɞɢɬɟ ɧɚ ɞɜɭɯ ɞɥɢɧɚɯ ɜɨɥɧ ɫɨ ɫɜɟɬɨɮɢɥɶɬɪɚɦɢ 440 ɢ                Ɍɢɨɫɟɪɧɚɹ ɤɢɫɥɨɬɚ H2S2O3 ɜ ɜɨɞɧɵɯ ɪɚɫɬɜɨɪɚɯ ɧɟɭɫɬɨɣɱɢɜɚ ɢ ɪɚɡɥɚɝɚ-
590 ɧɦ. Ɋɟɡɭɥɶɬɚɬɵ ɦɨɠɧɨ ɡɚɧɟɫɬɢ ɜ ɩɟɪɜɵɟ ɬɪɢ ɤɨɥɨɧɤɢ ɬɚɛɥɢɰɵ:                   ɟɬɫɹ ɫɨɝɥɚɫɧɨ ɭɪɚɜɧɟɧɢɸ
            Ɉɩɬɢɱɟɫɤɚɹ ɩɥɨɬɧɨɫɬɶ D          Ɋɚɜɧɨɜɟɫɧ. ɤɨɧɰ-ɹ, ɝ/ɥ                                       H2S2O3(ɪ.) ĺ SO2(ɪ.) + H2O + S(ɬɜ.).           (III.6)
      pH                                                             pKa
             440 ɧɦ       590 ɧɦ              HA            A–                   ȼ ɪɟɡɭɥɶɬɚɬɟ ɪɟɚɤɰɢɢ ɜɵɞɟɥɹɟɬɫɹ ɨɤɫɢɞ ɫɟɪɵ SO2, ɤɨɬɨɪɵɣ ɨɫɬɚɟɬɫɹ ɜ ɪɚɫ-
                                                                                 ɬɜɨɪɟ (ɪ.), ɢ ɧɟɪɚɫɬɜɨɪɢɦɚɹ ɜ ɜɨɞɟ ɫɟɪɚ. ɉɨɫɥɟɞɧɹɹ ɜɵɞɟɥɹɟɬɫɹ ɜ ɜɢɞɟ ɨɱɟɧɶ
                                                                                 ɦɟɥɤɢɯ ɬɜɟɪɞɵɯ ɱɚɫɬɢɰ, ɨɛɪɚɡɭɸɳɢɯ ɤɨɥɥɨɢɞɧɵɣ ɪɚɫɬɜɨɪ (ɡɨɥɶ).
                                                                                    Ʉɨɥɥɨɢɞɧɵɟ ɱɚɫɬɢɰɵ ɪɚɫɫɟɢɜɚɸɬ ɫɜɟɬ. ȼ ɪɟɡɭɥɶɬɚɬɟ ɨɩɬɢɱɟɫɤɚɹ ɩɥɨɬ-
    Ɉɛɪɚɛɨɬɤɚ ɪɟɡɭɥɶɬɚɬɨɜ. ɋɨɝɥɚɫɧɨ ɩɪɢɧɰɢɩɭ Ʌɟ ɒɚɬɟɥɶɟ ɜ ɳɺɥɨɱɧɨɦ               ɧɨɫɬɶ ɤɨɥɥɨɢɞɧɨɝɨ ɪɚɫɬɜɨɪɚ ɩɨɧɢɠɚɟɬɫɹ, ɞɚɠɟ ɟɫɥɢ ɜɟɳɟɫɬɜɨ ɧɟ ɢɦɟɟɬ
ɪɚɫɬɜɨɪɟ (ɩɪɢ pH > 9) ɞɨɦɢɧɢɪɭɟɬ ɞɢɫɫɨɰɢɢɪɨɜɚɧɧɚɹ ɮɨɪɦɚ A– ɛɪɨɦɬɢɦɨ-             ɫɨɛɫɬɜɟɧɧɨɣ ɨɤɪɚɫɤɢ. ȼ ɩɟɪɜɨɦ ɩɪɢɛɥɢɠɟɧɢɢ ɦɨɠɧɨ ɫɱɢɬɚɬɶ, ɱɬɨ ɨɩɬɢɱɟ-
ɥɨɜɨɝɨ ɫɢɧɟɝɨ. Ʉɨɧɰɟɧɬɪɚɰɢɟɣ ɧɟɞɢɫɫɨɰɢɢɪɨɜɚɧɧɵɯ ɦɨɥɟɤɭɥ HA ɦɨɠɧɨ                 ɫɤɚɹ ɩɥɨɬɧɨɫɬɶ ɩɪɨɩɨɪɰɢɨɧɚɥɶɧɚ ɱɢɫɥɭ ɪɚɫɫɟɢɜɚɸɳɢɯ n ɱɚɫɬɢɰ ɜ ɟɞɢɧɢɰɟ
ɩɪɟɧɟɛɪɟɱɶ. ɂɨɧɵ A– ɢɦɟɸɬ ɩɨɥɨɫɭ ɩɨɝɥɨɳɟɧɢɹ ɜ ɤɪɚɫɧɨɣ ɨɛɥɚɫɬɢ (ɫɦ.               ɨɛɴɟɦɚ: D  n. ɗɬɢɦ ɦɨɠɧɨ ɜɨɫɩɨɥɶɡɨɜɚɬɶɫɹ ɞɥɹ ɢɫɫɥɟɞɨɜɚɧɢɹ ɤɢɧɟɬɢɤɢ
ɪɢɫ. 6) ɢ ɨɤɪɚɲɟɧɵ ɜ ɫ ɢ ɧ ɢ ɣ ɰɜɟɬ. ȼ ɤɢɫɥɨɦ ɪɚɫɬɜɨɪɟ (ɩɪɢ pH < 5), ɧɚ-
                                                                                 ɪɟɚɤɰɢɢ (III.6), ɩɨɫɤɨɥɶɤɭ ɡɚɜɢɫɢɦɨɫɬɶ ɨɬ ɜɪɟɦɟɧɢ D(W) ɩɨɤɚɡɵɜɚɟɬ ɤɢɧɟ-
ɨɛɨɪɨɬ, ɩɪɢɫɭɬɫɬɜɭɸɬ ɦɨɥɟɤɭɥɵ HA, ɚ ɤɨɧɰɟɧɬɪɚɰɢɹ ɢɨɧɨɜ A– ɱɪɟɡɜɵɱɚɣɧɨ
                                                                                 ɬɢɤɭ ɧɚɤɨɩɥɟɧɢɹ ɨɞɧɨɝɨ ɢɡ ɩɪɨɞɭɤɬɨɜ ɪɟɚɤɰɢɢ. Ⱦɪɭɝɢɟ ɜɟɳɟɫɬɜɚ, ɭɱɚɫɬ-
ɦɚɥɚ. Ɉɤɚɡɵɜɚɟɬɫɹ, ɱɬɨ ɩɪɢ ɩɪɢɫɨɟɞɢɧɟɧɢɢ ɩɪɨɬɨɧɚ (A– + H+ ĺ HA) ɫɩɟɤɬɪ
                                                                                 ɜɭɸɳɢɟ ɜ ɪɟɚɤɰɢɢ, ɧɟ ɩɨɝɥɨɳɚɸɬ ɢ ɧɟ ɪɚɫɫɟɢɜɚɸɬ ɫɜɟɬ ɜ ɜɢɞɢɦɨɣ ɨɛɥɚɫɬɢ.
ɜɟɳɟɫɬɜɚ ɫɢɥɶɧɨ ɢɡɦɟɧɹɟɬɫɹ: ɢɫɱɟɡɚɟɬ ɤɪɚɫɧɚɹ ɩɨɥɨɫɚ ɩɨɝɥɨɳɟɧɢɹ ɢ ɩɨɹɜ-
                                                                                    ɐɟɥɶ ɪɚɛɨɬɵ. ɂɫɫɥɟɞɨɜɚɬɶ ɡɚɜɢɫɢɦɨɫɬɶ ɫɤɨɪɨɫɬɢ ɪɟɚɤɰɢɢ ɨɬ ɤɨɧɰɟɧ-
ɥɹɟɬɫɹ ɫɢɧɹɹ. Ɍɚɤɢɦ ɨɛɪɚɡɨɦ, ɤɢɫɥɚɹ ɮɨɪɦɚ ɨɤɪɚɲɟɧɚ ɜ ɨ ɪ ɚ ɧ ɠ ɟ ɜ ɨ-
                                                                                 ɬɪɚɰɢɢ ɩɪɟɜɪɚɳɚɸɳɟɝɨɫɹ ɜɟɳɟɫɬɜɚ. Ɉɩɪɟɞɟɥɢɬɶ ɷɧɟɪɝɢɸ ɚɤɬɢɜɚɰɢɢ ɪɟɚɤ-
ɤ ɪ ɚ ɫ ɧ ɵ ɣ ɰɜɟɬ.
                                                                                 ɰɢɢ ɪɚɡɥɨɠɟɧɢɹ ɬɢɨɫɟɪɧɨɣ ɤɢɫɥɨɬɵ.
    ɉɪɢ ɫɪɟɞɧɢɯ ɡɧɚɱɟɧɢɹɯ pH ɜ ɪɚɜɧɨɜɟɫɢɢ (III.4) ɩɪɢɫɭɬɫɬɜɭɸɬ ɨɛɟ ɮɨɪ-
ɦɵ – HA ɢ A–. ɂɡɦɟɪɹɹ ɨɩɬɢɱɟɫɤɭɸ ɩɥɨɬɧɨɫɬɶ ɧɚ ɞɥɢɧɟ ɜɨɥɧɵ 440, ɦɵ ɨɛ-
                                                                                    Ɉɛɨɪɭɞɨɜɚɧɢɟ ɢ ɪɟɚɤɬɢɜɵ.
ɧɚɪɭɠɢɜɚɟɦ ɩɟɪɜɭɸ ɢɡ ɷɬɢɯ ɮɨɪɦ; ɧɚ ɞɥɢɧɟ ɜɨɥɧɵ 590 ɧɦ – ɜɬɨɪɭɸ. ɉɨ                    Ɏɨɬɨɦɟɬɪ ɄɎɄ-5Ɇ ɫɨ ɫɜɟɬɨɮɢɥɶɬɪɨɦ 400 ɧɦ, 4 ɩɪɨɛɢɪɤɢ ɞɥɹ ɮɨɬɨɦɟɬɪɢɪɨɜɚɧɢɹ
ɡɚɤɨɧɭ Ȼɟɪɚ (II.5)                                                               (ɢɡ ɤɨɦɩɥɟɤɬɚ ɩɪɢɛɨɪɚ).
                     D440 = E440 ˜ [HA], D590 = E590 ˜ [A–].      (III.5)             ɋɟɤɭɧɞɨɦɟɪ.
                                                                                      Ɍɟɪɦɨɦɟɬɪ ɥɚɛɨɪɚɬɨɪɧɵɣ.
Ɉɬɫɸɞɚ ɦɨɠɧɨ ɨɩɪɟɞɟɥɢɬɶ ɪɚɜɧɨɜɟɫɧɵɟ ɤɨɧɰɟɧɬɪɚɰɢɢ. ɉɪɟɞɜɚɪɢɬɟɥɶɧɵɟ                     Ɋɚɫɬɜɨɪ ɬɢɨɫɭɥɶɮɚɬɚ ɧɚɬɪɢɹ 0,1 ɦɨɥɶ/ɥ.
(ɝɪɚɞɭɢɪɨɜɨɱɧɵɟ) ɢɡɦɟɪɟɧɢɹ ɩɨɤɚɡɵɜɚɸɬ, ɱɬɨ                                            Ɋɚɫɬɜɨɪ ɫɟɪɧɨɣ ɤɢɫɥɨɬɵ 0,1 ɦɨɥɶ/ɥ.
                                                                                      ȼɨɞɚ ɞɢɫɬɢɥɥɢɪɨɜɚɧɧɚɹ.
                        E440 = 20,46 ɥ/ɝ,    E590 = 41,74 ɥ/ɝ.                        4 ɫɬɚɤɚɧɚ ɟɦɤɨɫɬɶɸ 100 ɦɥ, 3 ɦɟɪɧɵɯ ɰɢɥɢɧɞɪɚ ɧɚ 50 ɦɥ.
                                                                                      2 ɛɨɥɶɲɢɟ ɩɪɨɛɢɪɤɢ.
   Ɉɩɪɟɞɟɥɟɧɢɟ ɤɨɧɫɬɚɧɬɵ pKa (ɩɟɪɜɵɣ ɫɩɨɫɨɛ). ɉɨ ɮɨɪɦɭɥɚɦ (III.5) ɜɵ-                 Ɍɟɪɦɨɫɬɚɬ ɢɥɢ ɜɨɞɹɧɚɹ ɛɚɧɹ.
ɱɢɫɥɢɬɟ ɪɚɜɧɨɜɟɫɧɵɟ ɤɨɧɰɟɧɬɪɚɰɢɢ [HA] ɢ [A–] ɞɥɹ ɤɚɠɞɨɝɨ ɢɡ ɢɫɫɥɟɞɨ-                  Ȼɭɦɚɠɧɵɟ ɮɢɥɶɬɪɵ.
ɜɚɧɧɵɯ ɡɧɚɱɟɧɢɣ pH. Ɋɟɡɭɥɶɬɚɬɵ ɡɚɧɟɫɢɬɟ ɜ ɬɚɛɥɢɰɭ. ɉɨ ɭɪɚɜɧɟɧɢɸ (III.3)
ɜɵɱɢɫɥɢɬɟ ɷɤɫɩɟɪɢɦɟɧɬɚɥɶɧɵɟ ɡɧɚɱɟɧɢɹ pKa, ɧɚɣɞɢɬɟ ɫɪɟɞɧɟɟ ɡɧɚɱɟɧɢɟ,                 ȼɵɩɨɥɧɟɧɢɟ ɪɚɛɨɬɵ. 1. ɉɨɞɝɨɬɨɜɶɬɟ ɮɨɬɨɦɟɬɪ ɤ ɢɡɦɟɪɟɧɢɹɦ ɨɩɬɢɱɟ-
ɚɛɫɨɥɸɬɧɭɸ ɢ ɨɬɧɨɫɢɬɟɥɶɧɭɸ ɩɨɝɪɟɲɧɨɫɬɢ.                                          ɫɤɨɣ ɩɥɨɬɧɨɫɬɢ. ɍɫɬɚɧɨɜɢɬɟ ɫɜɟɬɨɮɢɥɶɬɪ ɧɚ 400 ɧɦ. ȼ ɩɪɨɛɢɪɤɟ ɞɥɹ ɮɨɬɨ-
   ȼɬɨɪɨɣ ɫɩɨɫɨɛ. ɉɨɫɬɪɨɣɬɟ ɝɪɚɮɢɤɢ ɡɚɜɢɫɢɦɨɫɬɟɣ ɪɚɜɧɨɜɟɫɧɵɯ ɤɨɧɰɟɧ-             ɦɟɬɪɢɪɨɜɚɧɢɹ (ɧɚɯɨɞɢɬɫɹ ɜ ɤɨɦɩɥɟɤɬɟ ɩɪɢɛɨɪɚ) ɜ ɤɚɱɟɫɬɜɟ «ɯɨɥɨɫɬɨɣ ɩɪɨ-
ɬɪɚɰɢɣ [HA] ɢ [A–] ɨɬ pH ɜ ɨɞɧɨɣ ɤɨɨɪɞɢɧɚɬɧɨɣ ɫɟɬɤɟ. ɗɤɫɩɟɪɢɦɟɧɬɚɥɶɧɵɟ           ɛɵ» ɢɡɦɟɪɶɬɟ ɞɢɫɬɢɥɥɢɪɨɜɚɧɧɭɸ ɜɨɞɭ.
                                      35                                                                               36

Страницы