p-Xylene (data page)

This page provides supplementary chemical data on p-xylene.

Material Safety Data Sheet

The handling of this chemical may incur notable safety precautions. It is highly recommend that you seek the Material Safety Datasheet (MSDS) for this chemical from a reliable source and follow its directions.

MATHESON TRI-GAS, INC.

Structure and properties

Structure and properties
Index of refraction, n_D	1.4958 at 20 °C
Dielectric constant, ε_r	2.2 ε₀ at 20 °C
Surface tension	29.92 dyn/cm at 5 °C 28.27 dyn/cm at 20 °C 24.2 dyn/cm at 60 °C
Viscosity	0.7385 mPa·s at 10 °C 0.6475 mPa·s at 20 °C 0.5134 mPa·s at 40 °C 0.3519 mPa·s at 80 °C 0.2424 mPa·s at 130 °C
Solubility	0.160 g/L at 0 °C 0.181 g/L at 25 °C 0.22 g/L at 40 °C

Thermodynamic properties

Phase behavior
Triple point	286.3 K (13.15 °C), ? Pa
Critical point	617 K (344 °C), 3500 kPa
Std enthalpy change of fusion, Δ_fusH^o	17.1 kJ/mol
Std entropy change of fusion, Δ_fusS^o	59.8 J/(mol·K)
Std enthalpy change of vaporization, Δ_vapH^o	35.7 kJ/mol at 138 °C
Std entropy change of vaporization, Δ_vapS^o	? J/(mol·K)
Solid properties
Std enthalpy change of formation, Δ_fH^o_solid	? kJ/mol
Standard molar entropy, S^o_solid	? J/(mol K)
Heat capacity, c_p	? J/(mol K)
Liquid properties
Std enthalpy change of formation, Δ_fH^o_liquid	−24.4 kJ/mol
Standard molar entropy, S^o_liquid	247 J/(mol K)
Enthalpy of combustion, Δ_cH^o	−4552 kJ/mol
Heat capacity, c_p	181.7 J/(mol K)
Gas properties
Std enthalpy change of formation, Δ_fH^o_gas	1.796000E+04 kJ/kg-mol at 25 °C
Standard molar entropy, S^o_gas	? J/(mol K)
Heat capacity, c_p	163.2 J/(mol K) at 120 °C
van der Waals' constants	a = 3134 L² kPa/mol² b = 0.1809 liter per mole

Vapor pressure of liquid

P in mm Hg		1	10	40	100	400	760
T in °C		−8.1	27.3	54.4	75.9	115.9	138.3

Table data obtained from CRC Handbook of Chemistry and Physics 44th ed.

**log₁₀ of p-Xylene vapor pressure.** Uses formula: $\scriptstyle \log _{e}P_{mmHg}=$ $\scriptstyle \log _{e}({\frac {760}{101.325}})-9.527348\log _{e}(T+273.15)-{\frac {7637.951}{T+273.15}}+79.55720+5.748969\times 10^{-6}(T+273.15)^{2}$ obtained from CHERIC

Distillation data

BP Temp. °C	% by mole p-xylene
Vapor-liquid Equilibrium for p-Xylene/o-Xylene P = 26.66 kPa
BP Temp. °C	liquid	vapor
100.1	0.0	0.0
99.8	4.9	5.8
99.5	9.9	11.8
99.0	17.4	20.7
98.5	25.1	29.3
98.1	32.6	37.1
97.6	40.6	44.9
97.2	48.6	53.8
96.7	56.9	61.8
96.2	64.9	69.6
95.8	73.1	77.3
95.4	81.4	84.5
94.9	90.7	91.6
94.6	95.4	96.0
94.4	100.0	100.0

BP Temp. °C	% by mole p-xylene
Vapor-liquid Equilibrium for p-Xylene/m-Xylene P = 26.66 kPa
BP Temp. °C	liquid	vapor
95.30	0.0	0.0
95.20	8.3	8.5
95.15	15.5	15.8
95.05	24.3	24.9
95.00	33.0	33.6
94.90	40.9	41.7
94.85	49.0	49.7
94.75	57.1	57.9
94.70	65.3	66.1
94.60	73.8	74.3
94.55	81.7	82.2
94.50	89.5	89.9
94.45	94.8	94.8
94.40	100.0	100.0

BP Temp. °C	% by mole carbon tetrachloride
Vapor-liquid Equilibrium for p-Xylene/carbon tetrachloride P = 760 mm Hg
BP Temp. °C	liquid	vapor
136.4	1.7	5.9
131.1	6.3	21.6
126.2	11.1	34.9
121.8	15.7	45.3
117.6	20.3	53.9
113.5	25.2	61.6
109.8	30.1	67.9
106.2	35.1	73.1
102.7	40.5	77.9
102.2	41.3	78.7
98.1	48.5	83.6
94.4	55.8	87.6
91.1	62.9	90.8
88.0	70.1	93.4
85.2	77.2	95.4
82.6	84.0	96.9
80.0	91.1	98.4
77.6	97.7	99.7

BP Temp. °C	% by mole butanone
Vapor-liquid Equilibrium for p-Xylene/Butanone P = 760 mm Hg
BP Temp. °C	liquid	vapor
129.45	4.8	20.8
125.42	7.9	31.7
123.25	10.2	38.1
116.80	16.1	51.1
112.44	21.0	59.4
105.55	30.5	71.0
101.15	38.7	75.5
95.30	50.6	85.2
93.90	54.6	87.2
89.45	67.0	91.7
86.55	77.0	94.7
85.02	81.5	95.9
84.58	83.1	96.2
80.65	97.0	994

BP Temp. °C	% by mole p-xylene
Vapor-liquid Equilibrium for p-Xylene/Aniline P = 745 mm Hg
BP Temp. °C	liquid	vapor
171	7.5	37.0
165	14.0	50.0
156	26.5	67.5
148	48.5	80.0
142	72.5	89.0
140	83.0	92.0

Spectral data

UV-Vis
Spectrum
λ_max	? nm
Extinction coefficient, ε	?
IR
Spectrum	NIST
Major absorption bands	793.94 cm⁻¹
NMR
Spectrum	AIST^{[permanent dead link]}
Proton NMR	2.296, 7.046
Carbon-13 NMR	134.66, 128.97, 20.90
MS
Spectrum	NIST
Masses of main fragments	106, 91, 77

This box:

Except where noted otherwise, data relate to Standard temperature and pressure.
Reliability of data general note.

References

Notes

Bibliography

NIST Standard Reference Database
"University of Akron, Chemistry Department, Chemical Database". Archived from the original on 13 January 2004. Retrieved 1 February 2007.
"National Institute of Advanced Industrial Science and Technology". Archived from the original on 5 May 2006. Retrieved 1 February 2007.