Surface Chemistry and Colloid

博客与笔记二相性

有意思的物理化学课awww。

Surface Chemistry

Adsorption Isotherms

Langmuir isotherms

Adsorption cannot proceed beyond monolayer coverage.
=> 单层吸附
All sites on the surface are equivalent.
=> 表面均一，各点等同
A molecule can be adsorbed only at a vacant site.
=> 吸附只发生在空位点
The probability of adsorption is independent of the occupation of neighboring sites (that is, there are no interactions between adsorbed molecules).
=> 分子间不发生相互作用

BET iostherms

表面不均一
分子间可以存在相互作用
可以发生多层吸附

Colloid

Colloid Types

Dispersed Substance	Dispersion Medium	Colloid Type	Examples
Liquid	Gas	Aerosol	Fog, mist, disinfectant spray
Solid	Gas	Aerosol	Smoke, dust in the air
Gas	Liquid	Foam	Whipped cream, shaving cream
Gas	Solid	Foam	Marshmallow, polystyrene foam
Solid	Liquid	Gel or sols	Glue, paint, gelatin, blood, gels.
Liquid	Liquid	Emulsion	Milk, mayonnaise

Tyndall Effect: Scattering of light by dispersed particles

Appendix

贴一张做作业时随手写的程序实现，详见 repo。

import matplotlib.pyplot as plt
import numpy as np
import scipy.stats as stats

def useLangmuir(data):
  x = data[0]
  y = data[0] / data[1]

  plt.plot(x, y, 'o', label='data')

  slope, intercept = stats.linregress(x, y)[:2]

  Max = 1 / slope
  print(f'Max: {Max}')

  K = slope / intercept
  print(f'K: {K}')

  _x = np.linspace(min(x), max(x), 100)
  _y = slope * _x + intercept

  plt.plot(_x, _y, label=f'y = {slope:.8f}x + {intercept:.8f}')

  plt.legend()
  plt.show()

  return (Max, K)


def useBET(data, p0=76):
  x = data[0] / p0
  y = x / (data[1] * (x - 1))

  plt.plot(x, y, 'o', label='data')

  slope, intercept = stats.linregress(x, y)[:2]

  c = slope / intercept - 1
  print(f'c: {c}')

  mom = 1 / c / intercept
  print(f'mom: {mom}')

  _x = np.linspace(min(x), max(x), 100)
  _y = slope * _x + intercept

  plt.plot(_x, _y, label=f'y = {slope:.8f}x + {intercept:.8f}')

  plt.legend()
  plt.show()

  return (mom, c)

图片均取自陆奇老师的 PPT。