Mollier Chart of Iso-Butane

Mollier Chart of Normal Butane

Mollier Chart of Propane

Properties of Propane and Butane

Calculating Vapor Pressures of Mixtures

Component	% vol. at 70°F	lb/gal. at 70°F	lb. per 100 gal. at 70°F	% mass
	a	b	c =a * b	d = 100 * c / total c
Ethane	0.57	3.200	1.824	0.41
Propane	30.94	4.175	129.175	28.69
Isobutane	62.69	4.646	291.258	64.70
N-butane	5.80	4.817	27.939	6.20
Totals	100.00		450.196	100.00
Component	Molecular mass	lb.mols/ 100 gal.	Mol fraction	Vapor pressure at 70°F absolute, psi
	e	f=d / e	g = f / total f	h
Ethane	30.068	0.061	0.007	570
Propane	44.094	2.93	0.345	124
Isobutane	58.120	5.011	0.591	46
N-butane	58.120	0.481	0.057	31
Totals		8.483	1.000
Component	Partial Pressure absolute, psi		Composition of vapor in equilibrium with liquid % by vol.
	i=g * h		j = 100 * i / total i
Ethane	3.99		5.27
Propane	42.78		56.50
Isobutane	27.19		35.90
N-butane	1.77		2.33
Totals	75.72		100.00

Flame Temperatures of Hydrocarbon Gases

	Flame Temperature		Flame Speed in 1" Tube
	°F	°C	in/s	m/s
Methane	3416	1880	26	0.66
Ethane	3443	1895	34	0.86
Propane	3497	1925	32	0.81
N-butane	3443	1895	33	0.84
Isobutane	3452	1900	33	0.84
Ethylene	3587	1975	65	1.65
Propylene	3515	1935	39	0.99
Butylene	3506	1930	38	0.97

Physical Properties of Hydrocarbons

NAME	METHANE	ETHENE	ETHANE	PROPENE	PROPANE	ISO-BUTANE	BUTENE-I	ISO-BUTENE	N-BUTANE	ISO-PENTANE	PENTENE-I	N-PENTANE
FORMULA	CH4	C2H4	C2H6	C3H6	C3H8	C4H10	C4H8	C4H8	C4H10	C5H12	C5H10	C5H12
Vapor pressure at 100F/17,8C
psi, gauge				212.5	175.8	57.5	47.6	48.9	36.9	5.7		0.9
psi, absolute			780.0	227.2	190.0	72.2	62.3	63.6	51.6	20.4	19.4	15.6
bar, gauge				14.7	12.1	4.0	3.3	3.4	2.5	0.4		0.1
kilopascal, absolute			5374.2	1565.4	1309.1	497.5	429.2	438.2	355.5	140.6	133.7	107.5
Normal state at 60F/15,6C and atmospheric pressure	gas	gas	gas	gas	gas	gas	gas	gas	gas	liquid	liquid	liquid
Boiling point at atmospheric pressure
Fahrenheit	-258.7	-154.7	-127.5	-53.9	-43.7	10.9	20.7	19.6	31.1	82.1	85.9	96.9
Celsius	-161.5	-103.7	-88.6	-47.7	-42.1	-11.7	-6.3	-6.9	-0.5	27.9	30.0	36.1
Weight of liquid at 60F/15,6C
pound/US gal	2.50	3.30	3.11	4.35	4.23	4.69	5.01	5.00	4.86	5.20	5.39	5.25
kg/m3	300	395	373	521	507	562	600	600	582	623	646	629
Specific gravity (water=1)	0.300		0.374	0.522	0.508	0.563	0.601	0.600	0.584	0.625	0.646	0.631
API gravity	340.0		247.0	139.7	147.2	119.8	103.9	104.3	110.6	95.0	87.5	92.7
Weight of vapor at 60F/15,6C and atmospheric pressure
pound/100 cubic feet	4.23	7.39	7.92	11.09	11.62	15.31	14.79	14.79	15.31	19.01		19.01
kg/m3	0.68	1.18	1.27	1.78	1.86	2.45	2.37	2.37	2.45	3.05		3.05
Gross heat of combustion
BTU/pound	23891	21650	22329	21060	21670	21265	20860	20740	21315	21046	20720	21094
BTU/cubic foot vapor @ 60F	1012	1601	1783	2335	2558	3354	3084	3066	3368	4003	3829	4015
BTU/US gallon liquid @ 60F		70910	69433	87740	91044	99097	103480	104060	103047	108820	110850	110125
kcal/kg	13260	12016	12393	11688	12027	11802	11577	11511	11830	11681	11500	11707
kcal/m3 vapor @ 15,6C	9012	14257	15878	20793	22779	29867	27463	27303	29992	35647	34097	35754
kcal/litre liquid @ 15,6C		4723	4624	5843	6064	6600	6892	6930	6863	7247	7383	7334
MJ/kg	55.48	50.27	51.85	48.90	50.32	49.38	48.44	48.16	49.50	48.87	48.11	48.98
MJ/m3 vapor @ 15,6C	37.71	59.65	66.43	87.00	95.31	124.97	114.91	114.23	125.49	149.15	142.66	149.59
MJ/litre liquid @ 15,6C	0.00	19.76	19.35	24.45	25.37	27.61	28.84	29.00	28.71	30.32	30.89	30.69
Air to burn gas
volume/volume vapor ratio @ 60F/15.6C, atmospheric pressure	9.53	14.29	16.67	21.44	23.82	30.97	28.58	28.58	30.97	38.11	35.73	38.11
mass/mass ratio	17.24	14.76	16.13	14.76	15.71	15.49	14.76	14.76	15.49	15.35	14.76	15.35
Flammability limits
Lower % in air	5.0	3.2	3.0	2.0	2.4	1.8			1.9	1.3	1.6	1.4
Upper % in air	15.0	12.5	15.0	11.0	9.5	8.4			8.4			7.8
Heat required to vaporize liquid at boiling point and atmospheric pressure
BTU/pound	245	208	211	189	183	158	174	167	166	146	148	153
BTU/US gallon liquid	712	686	696	822	774	741	872	836	797	759	797	803
kcal/kg	136.0	115.4	117.1	104.9	101.6	87.7	96.6	92.7	92.1	81.0	82.1	84.9
kcal/litre liquid	47.4	45.7	46.4	54.7	51.5	49.4	58.1	55.7	53.1	50.5	53.1	53.5
Molecular Mass	16.042	28.052	30.068	42.079	44.094	58.120	56.105	56.105	56.105	58.120	72.146	70.131
Specific heat at 60F/15,6C and atmospheric pressure
BTU/lb.F
Cp liquid							0.540	0.555	0.550	0.533		0.536
Cp vapor	0.527	0.362	0.410	0.352	0.389	0.387	0.347		0.397	0.388		0.397
Cv vapor	0.402	0.288	0.343	0.298	0.342	0.352	0.303		0.363	0.361		0.370
Cp/Cv vapor	1.308	1.258	1.193	1.180	1.133	1.097	1.145		1.094	1.076		1.074
KJ/kg.K
Cp liquid							2.261	2.324	2.303	2.232		2.244
Cp vapor	2.207	1.516	1.717	1.474	1.629	1.620	1.453		1.662	1.624		1.662
Cv vapor	1.683	1.206	1.436	1.248	1.432	1.474	1.269		1.520	1.511		1.549
Cp/Cv vapor	5.476	5.267	4.995	4.940	4.744	4.593	4.794		4.580	4.505		4.497
Critical Conditions
Temperature, Fahrenheit	-116.5	49.8	90.1	196.5	206.2	273.2	297.0	292.5	305.6	370.0	394.0	387.0
Temperature, Celsius	-82.5	9.9	32.3	91.4	96.8	134.0	147.2	144.7	152.0	187.6	201.0	197.2
Pressure, psi(a)	673	742	708	667	617	529	588	580	551	483	594	490
Pressure, bar(a)	46.4	51.2	48.8	46.0	42.5	36.5	40.5	40.0	38.0	33.3	41.0	33.8
Density, lbs/US gal	1.351		1.695		1.888	1.946			1.891	1.955		1.935
Density, kg/m3	161.9		203.1		226.2	233.2			226.6	234.3		231.9