Per cent by weight.

Per cent.

by volume at 15°.

Differences.

0

0.000

1.253

1

1.253

1.249

2

2.502

1.244

3

3.746

1.240

4

4.986

1.236

5

6.222

Per cent. by weight.

Per cent.

by volume at 15°.

Differences.

5

6.222

1.232

6

7.454

1.228

7

8.682

1.225

8

9.907

1.221

9

11.128

1.217

10

12.345

Per cent. by weight.

Per cent.

by volume at 15°.

Differences.

10

12.345

1.214

11

12.559

1.211

12

14.770

1.207

13

15.977

1.204

14

17181

1.201

15

18.382

1.197

16

19.579

1.194

17

20.773

1.190

18

21.963

1.186

19

23.149

1.183

20

24.332

1.180

21

25.512

1.176

22

26.688

1.172

23

27.860

1.169

24

29029

1.164

25

30.193

1.161

26

31.364

1.166

27

32.510

1.162

28

33.662

1.147

29

34.809

1.143

30

35.952

1.139

31

37.091

1.133

32

38.224

1.128

33

39.352

1.124

34

40.470

1.118

35

41.594

1.114

36

42.708

1.108

37

43.816

1.103

38

44.919

1.097

39

46016

1.093

40

47.109

1.086

41

48.195

1.082

42

49.277

1.076

43

50.353

1.069

44

51.422

1.064

45

52.486

1.058

46

53.544

1.051

47

54.595

1.044

48

55.639

1.039

49

56.678

1.034

50

57.712

1.027

51

58.739

1.020

52

59.759

1.014

53

60.773

1.008

54

61.781

1.002

55

62.783

Per cent. by weight.

Per cent.

by volume at 15°.

Differences.

55

62.783

0.996

56

63.778

0.989

57

64.767

0.983

58

65.750

0.975

59

66.725

0.968

60

67.693

0.961

61

68.654

0.953

62

69.607

0.946

63

70.552

0.938

64

71.490

0.930

65

72.420

0.924

66

73.344

0.918

67

74.262

0.910

68

75.172

0.905

69

76.077

0.899

70

76.976

0.888

71

77.864

0.882

72

78.746

0.872

73

79.618

0.862

74

80.480

0.856

75

81.336

0.846

76

82.182

0.840

77

83.022

0.833

78

83.856

0.825

79

84.680

0.819

80

85.499

0.811

81

86.310

0.800

82

87110

0.789

S3

87.899

0.778

84

88.677

0.771

85

89.448

0.764

86

90.212

0.756

87

90.968

0.748

88

91.716

0.740

89

92.456

0.732

90

93.188

0.724

91

93.912

0.715

92

94.627

0.699

93

95.326

0.691

94

96.017

0.680

95

96.697

0.673

96

97.370

0.666

97

98036

0.660

98

98.696

0.655

99

99.351

0.649

100

100.000

Boiling points of mixtures of methyl alcohol and water.* by weight.

Methyl alcohol.

Per cent.

B.p. at 700 mm.

B.p. at

760 mm.

B.p. at 800 mm.

0

97.72°

100°

101.44°

10

89.51

91.72

93.14

20

83.97

86.16

87.57

30

80.00

82.17

83.56

40

76.97

79.10

80.48

50

74.44

76.54

77.91

60

72.17

74.29

75.65

70

69.98

72.08

73.44

80

67.77

69.87

71.22

90

65.32

67.40

68.75

100

62.53

64.57

65.92

* Doroschewsky and Poljansky, J. Buss. Phys. Chem. Ges., 1910, 42, 109 - 134.

The vapour pressure and heat of vaporisation of methyl alcohol at various temperatures up to the critical point are shown in the following table (slightly abbreviated) due to S. Young.1

Methyl alcohol.

Temp.

Vapour pressure, mm.

Heat of vaporisation, calories.

29.6

289.17

10

54.7

287.36

20

96.0

284.54

30

160.0

282.07

40

260.5

277.78

50

406.0

27414

60

625.0

269.41

70

-

264.51

80

1341

258.96

90

1897

252.76

100

2621

246.01

120

4751

232.00

140

8071

216.12

160

13027

198.34

180

20089

177.16

200

29787

151.84

220

42573

112.53

230

50414

84.47

232

52202

77.73

234

53939

70.15

236

55624

61.66

238

57576

50.22

238.5

58329

44.23

239

58741

-

239.5

59145

-

240

59660

0

Critical temp.

The specific heat of methyl alcohol at temperatures from 18° to 100° is 0 6581 (Doroschewsky). This investigator has also deter.

1 Sclent. Proc. Roy. Dublin Soc. [N.S.], 1910, 12, 440.

mined the specific heats of mixtures of methyl alcohol and water over the range 18° to 1000,1 the results being as follows: -

Per cent, of methyl alcohol by weight.

Specific heat.

90.01 ..........

0.7200

80.00 ..........

0.7744

69.99 . . ........

0.8287

60.03 ..........

0.8689

49.98 ..........

0.9162

40.00 ..........

0.9542

30.02 ..........

0.9871

24.98 ..........

1.0001

20.00 ..........

1.0021

15.01 ..........

1.0065

10.01 .. .. ......

1.0114

5.00 ..........

1.0085

0.00 (water) ........

1.0060

The viscosity of methyl alcohol at 20° is 0005072; at 25°, 0 00564; and at 45°, 0.00424. The molecular magnetic rotation is 1.640.2

Oxidising agents convert methyl alcohol into formaldehyde and then into formic acid, and ultimately under certain conditions into carbon dioxide and water. Examples of each of these reactions are described in Chap. VI in connection with the estimation of methyl alcohol.

When heated with soda.lime, methyl alcohol yields sodium formate: -

CH3.OH + NaOH = H. COONa + 2H1.

In certain crystalline compounds, methyl alcohol functions as alcohol of crystallisation. The most noteworthy is the combination with calcium chloride, CaCl2,4CH4O, which crystallises in hexagonal plates, and is obtained by the direct union of the alcohol and the calcium salt. Lithium chloride and magnesium chloride supply other examples of such combinations. Magnesium itself dissolves in warm methyl alcohol, giving the methoxide in crystals which contain 3 molecules of the alcohol. Barium oxide is dissolved by methyl alcohol to give the crystalline compound BaO,2CH4O,2H1O.

Electrolysis. . On electrolysing methyl alcohol in aqueous sulphuric acid, hydrogen is evolved, and oxidation products are formed. These consist of methyl formate, methylal, methyl acetate, acetic acid, and methyl sulphuric acid, with a little carbon dioxide and carbon monoxide. Under special conditions, formaldehyde is produced.

1 J. Russ. Phys. Chem. Ges., 1909, 41, 958; Chem. Zentr., 1910, l, 156.

2 Perkin, Trans. Chem. Soc, 1902, 81, 178.

In aqueous solution, on addition of potassium acetate, methane and potassium methyl carbonate are produced, as well as the carbon oxides.

Electrolysed without a solvent, either alone or with the addition of a lit le alkali, methyl alcohol yields chiefly carbon dioxide, together with monoxide, oxygen, and hydrogen. In presence of alkali, carbonate of the latter is formed.