Enthalpy Of Formation Of Water

Modify of enthalpy during the formation of a compound from its elements

In chemistry and thermodynamics, the standard enthalpy of formation or standard heat of germination of a compound is the change of enthalpy during the formation of 1 mole of the substance from its constituent elements, with all substances in their standard states. The standard pressure value p ^⦵ = ten^five Pa (= 100 kPa = 1 bar) is recommended by IUPAC, although prior to 1982 the value 1.00 atm (101.325 kPa) was used.^[ane] There is no standard temperature. Its symbol is Δ_f H ^⦵ . The superscript Plimsoll on this symbol indicates that the procedure has occurred nether standard conditions at the specified temperature (normally 25 °C or 298.15 K). Standard states are as follows:

1. For a gas: the hypothetical state information technology would have bold it obeyed the platonic gas equation at a pressure of ane bar
2. For a gaseous or solid solute nowadays in a diluted ideal solution: the hypothetical state of concentration of the solute of exactly i mole per liter (one M) at a pressure level of i bar extrapolated from infinite dilution
3. For a pure substance or a solvent in a condensed state (a liquid or a solid): the standard state is the pure liquid or solid under a pressure of i bar
4. For an chemical element: the form in which the element is near stable under 1 bar of pressure. One exception is phosphorus, for which the well-nigh stable form at 1 bar is black phosphorus, but white phosphorus is chosen as the standard reference state for zero enthalpy of formation.^[2]

For example, the standard enthalpy of formation of carbon dioxide would be the enthalpy of the following reaction under the above conditions:

${\displaystyle {\ce {C(southward, graphite) + O2(1000) -> CO2(thou)}}}$

All elements are written in their standard states, and one mole of product is formed. This is true for all enthalpies of formation.

The standard enthalpy of germination is measured in units of energy per amount of substance, unremarkably stated in kilojoule per mole (kJ mol⁻ⁱ), but also in kilocalorie per mole, joule per mole or kilocalorie per gram (any combination of these units befitting to the energy per mass or corporeality guideline).

All elements in their standard states (oxygen gas, solid carbon in the course of graphite, etc.) have a standard enthalpy of formation of cipher, as in that location is no change involved in their germination.

The formation reaction is a abiding pressure and constant temperature process. Since the pressure of the standard formation reaction is stock-still at 1 bar, the standard formation enthalpy or reaction heat is a function of temperature. For tabulation purposes, standard formation enthalpies are all given at a single temperature: 298 K, represented by the symbol Δ_f H ^⦵
_{298 Chiliad} .

Hess's police force [edit]

For many substances, the germination reaction may exist considered as the sum of a number of simpler reactions, either real or fictitious. The enthalpy of reaction tin can then be analyzed by applying Hess's Law, which states that the sum of the enthalpy changes for a number of private reaction steps equals the enthalpy change of the overall reaction. This is truthful because enthalpy is a state role, whose value for an overall process depends simply on the initial and final states and not on whatever intermediate states. Examples are given in the post-obit sections.

Ionic compounds: Born–Haber cycle [edit]

Standard enthalpy change of formation in Born–Haber diagram for lithium fluoride. ΔH _latt corresponds to U_L in the text. The downward pointer "electron affinity" shows the negative quantity –EA_F , since EA_F is ordinarily defined as positive.

For ionic compounds, the standard enthalpy of formation is equivalent to the sum of several terms included in the Born–Haber bike. For instance, the formation of lithium fluoride,

${\displaystyle {\ce {Li(s) + 1/2F2(g) -> LiF(south)}}}$

may be considered as the sum of several steps, each with its ain enthalpy (or energy, approximately):

1. H _sub , the standard enthalpy of atomization (or sublimation) of solid lithium.
2. IE_Li , the first ionization energy of gaseous lithium.
3. B(F–F), the standard enthalpy of atomization (or bail free energy) of fluorine gas.
4. EA_F , the electron affinity of a fluorine atom.
5. U_Fifty , the lattice energy of lithium fluoride.

The sum of all these enthalpies will give the standard enthalpy of formation (ΔH _f ) of lithium fluoride:

${\displaystyle \Delta H_{\text{f}}=\Delta H_{\text{sub}}+{\text{IE}}_{\text{Li}}+{\frac {1}{2}}{\text{B(F–F)}}-{\text{EA}}_{\text{F}}+{\text{U}}_{\text{50}}.}$

In practice, the enthalpy of formation of lithium fluoride tin exist determined experimentally, simply the lattice energy cannot be measured directly. The equation is therefore rearranged in gild to evaluate the lattice energy:^[3]

${\displaystyle -U_{\text{Fifty}}=\Delta H_{\text{sub}}+{\text{IE}}_{\text{Li}}+{\frac {one}{ii}}{\text{B(F–F)}}-{\text{EA}}_{\text{F}}-\Delta H_{\text{f}}.}$

Organic compounds [edit]

The formation reactions for virtually organic compounds are hypothetical. For instance, carbon and hydrogen won't directly react to class methane (CH₄ ), then that the standard enthalpy of formation cannot be measured directly. Still the standard enthalpy of combustion is readily measurable using bomb calorimetry. The standard enthalpy of formation is then adamant using Hess'south law. The combustion of methane:

${\displaystyle {\ce {CH4 + 2 O2 -> CO2 + 2 Water}}}$

is equivalent to the sum of the hypothetical decomposition into elements followed past the combustion of the elements to form carbon dioxide (CO₂ ) and h2o (H₂O):

${\displaystyle {\ce {CH4 -> C + 2H2}}}$

${\displaystyle {\ce {C + O2 -> CO2}}}$

${\displaystyle {\ce {2H2 + O2 -> 2H2O}}}$

Applying Hess's law,

${\displaystyle \Delta _{\text{rummage}}H^{\ominus }({\text{CH}}_{4})=[\Delta _{\text{f}}H^{\ominus }({\text{CO}}_{2})+two\Delta _{\text{f}}H^{\ominus }({\text{H}}_{two}{\text{O}})]-\Delta _{\text{f}}H^{\ominus }({\text{CH}}_{4}).}$

Solving for the standard of enthalpy of formation,

${\displaystyle \Delta _{\text{f}}H^{\ominus }({\text{CH}}_{four})=[\Delta _{\text{f}}H^{\ominus }({\text{CO}}_{ii})+2\Delta _{\text{f}}H^{\ominus }({\text{H}}_{2}{\text{O}})]-\Delta _{\text{rummage}}H^{\ominus }({\text{CH}}_{4}).}$

The value of ${\displaystyle \Delta _{\text{f}}H^{\ominus }({\text{CH}}_{4})}$ is determined to be −74.viii kJ/mol. The negative sign shows that the reaction, if it were to proceed, would exist exothermic; that is, methane is enthalpically more stable than hydrogen gas and carbon.

It is possible to predict heats of formation for elementary unstrained organic compounds with the heat of formation grouping additivity method.

Use in calculation for other reactions [edit]

The standard enthalpy change of any reaction can be calculated from the standard enthalpies of formation of reactants and products using Hess'southward constabulary. A given reaction is considered every bit the decomposition of all reactants into elements in their standard states, followed by the formation of all products. The heat of reaction is so minus the sum of the standard enthalpies of formation of the reactants (each existence multiplied past its corresponding stoichiometric coefficient, ν) plus the sum of the standard enthalpies of formation of the products (each also multiplied by its corresponding stoichiometric coefficient), as shown in the equation below:^[iv]

${\displaystyle \Delta _{\text{r}}H^{\ominus }=\sum \nu \Delta _{\text{f}}H^{\ominus }({\text{products}})-\sum \nu \Delta _{\text{f}}H^{\ominus }({\text{reactants}}).}$

If the standard enthalpy of the products is less than the standard enthalpy of the reactants, the standard enthalpy of reaction is negative. This implies that the reaction is exothermic. The antipodal is also true; the standard enthalpy of reaction is positive for an endothermic reaction. This calculation has a tacit supposition of ideal solution between reactants and products where the enthalpy of mixing is nix.

For instance, for the combustion of methane, ${\displaystyle {\ce {CH4 + 2O2 -> CO2 + 2H2O}}}$ :

${\displaystyle \Delta _{\text{r}}H^{\ominus }=[\Delta _{\text{f}}H^{\ominus }({\text{CO}}_{2})+2\Delta _{\text{f}}H^{\ominus }({\text{H}}_{2}{\text{O}})]-\Delta _{\text{f}}H^{\ominus }({\text{CH}}_{iv})+2\Delta _{\text{f}}H^{\ominus }({\text{O}}_{2})].}$

However ${\displaystyle {\ce {O2}}}$ is an element in its standard state, so that ${\displaystyle \Delta _{\text{f}}H^{\ominus }({\text{O}}_{2})=0}$ , and the heat of reaction is simplified to

${\displaystyle \Delta _{\text{r}}H^{\ominus }=[\Delta _{\text{f}}H^{\ominus }({\text{CO}}_{2})+2\Delta _{\text{f}}H^{\ominus }({\text{H}}_{2}{\text{O}})]-\Delta _{\text{f}}H^{\ominus }({\text{CH}}_{4}),}$

which is the equation in the previous section for the enthalpy of combustion ${\displaystyle \Delta _{\text{comb}}H^{\ominus }}$ .

Central concepts for doing enthalpy calculations [edit]

1. When a reaction is reversed, the magnitude of ΔH stays the aforementioned, but the sign changes.
2. When the balanced equation for a reaction is multiplied by an integer, the respective value of ΔH must be multiplied by that integer likewise.
3. The alter in enthalpy for a reaction tin can exist calculated from the enthalpies of formation of the reactants and the products
4. Elements in their standard states brand no contribution to the enthalpy calculations for the reaction, since the enthalpy of an element in its standard state is zero. Allotropes of an element other than the standard land more often than not have non-zero standard enthalpies of formation.

Examples: standard enthalpies of formation at 25 °C [edit]

Thermochemical properties of selected substances at 298.15 K and 1 atm

Inorganic substances [edit]

Species	Phase	Chemical formula	Δf H ⦵ /(kJ/mol)
Aluminium
Aluminium	Solid	Al	0
Aluminium chloride	Solid	AlClthree	−705.63
Aluminium oxide	Solid	AliiOthree	−1675.5
Aluminium hydroxide	Solid	Al(OH)3	−1277
Aluminium sulphate	Solid	Al2(SO4)3	−3440
Barium
Barium chloride	Solid	BaCl2	−858.vi
Barium carbonate	Solid	BaCO3	−1216
Barium hydroxide	Solid	Ba(OH)2	−944.7
Barium oxide	Solid	BaO	−548.1
Barium sulfate	Solid	BaSO4	−1473.3
Beryllium
Glucinium	Solid	Be	0
Beryllium hydroxide	Solid	Be(OH)ii	−903
Beryllium oxide	Solid	BeO	−609.4
Boron
Boron trichloride	Solid	BCl3	−402.96
Bromine
Bromine	Liquid	Br2	0
Bromide ion	Aqueous	Br−	−121
Bromine	Gas	Br	111.884
Bromine	Gas	Br2	thirty.91
Bromine trifluoride	Gas	BrFiii	−255.lx
Hydrogen bromide	Gas	HBr	−36.29
Cadmium
Cadmium	Solid	Cd	0
Cadmium oxide	Solid	CdO	−258
Cadmium hydroxide	Solid	Cd(OH)2	−561
Cadmium sulfide	Solid	CdS	−162
Cadmium sulfate	Solid	CdSOfour	−935
Caesium
Caesium	Solid	Cs	0
Caesium	Gas	Cs	76.fifty
Caesium	Liquid	Cs	2.09
Caesium(I) ion	Gas	Cs+	457.964
Caesium chloride	Solid	CsCl	−443.04
Calcium
Calcium	Solid	Ca	0
Calcium	Gas	Ca	178.2
Calcium(2) ion	Gas	Ca2+	1925.90
Calcium(II) ion	Aqueous	Ca2+	−542.vii
Calcium carbide	Solid	CaC2	−59.eight
Calcium carbonate (Calcite)	Solid	CaCO3	−1206.9
Calcium chloride	Solid	CaCl2	−795.8
Calcium chloride	Aqueous	CaClii	−877.3
Calcium phosphate	Solid	Cathree(POiv)2	−4132
Calcium fluoride	Solid	CaF2	−1219.6
Calcium hydride	Solid	CaH2	−186.2
Calcium hydroxide	Solid	Ca(OH)2	−986.09
Calcium hydroxide	Aqueous	Ca(OH)ii	−1002.82
Calcium oxide	Solid	CaO	−635.09
Calcium sulfate	Solid	CaSOiv	−1434.52
Calcium sulfide	Solid	CaS	−482.iv
Wollastonite	Solid	CaSiO3	−1630
Carbon
Carbon (Graphite)	Solid	C	0
Carbon (Diamond)	Solid	C	ane.ix
Carbon	Gas	C	716.67
Carbon dioxide	Gas	COtwo	−393.509
Carbon disulfide	Liquid	CStwo	89.41
Carbon disulfide	Gas	CStwo	116.7
Carbon monoxide	Gas	CO	−110.525
Carbonyl chloride (Phosgene)	Gas	COCl2	−218.viii
Carbon dioxide (un–ionized)	Aqueous	CO2(aq)	−419.26
Bicarbonate ion	Aqueous	HCO3 –	−689.93
Carbonate ion	Aqueous	CO3 two–	−675.23
Chlorine
Monatomic chlorine	Gas	Cl	121.7
Chloride ion	Aqueous	Cl−	−167.2
Chlorine	Gas	Cltwo	0
Chromium
Chromium	Solid	Cr	0
Copper
Copper	Solid	Cu	0
Copper(II) oxide	Solid	CuO	−155.2
Copper(II) sulfate	Aqueous	CuSO4	−769.98
Fluorine
Fluorine	Gas	Ftwo	0
Hydrogen
Monatomic hydrogen	Gas	H	218
Hydrogen	Gas	H2	0
Water	Gas	HiiO	−241.818
H2o	Liquid	H2O	−285.8
Hydrogen ion	Aqueous	H+	0
Hydroxide ion	Aqueous	OH−	−230
Hydrogen peroxide	Liquid	HtwoO2	−187.8
Phosphoric acid	Liquid	H3PO4	−1288
Hydrogen cyanide	Gas	HCN	130.5
Hydrogen bromide	Liquid	HBr	−36.three
Hydrogen chloride	Gas	HCl	−92.30
Hydrogen chloride	Aqueous	HCl	−167.2
Hydrogen fluoride	Gas	HF	−273.3
Hydrogen iodide	Gas	HI	26.5
Iodine
Iodine	Solid	Iii	0
Iodine	Gas	Iii	62.438
Iodine	Aqueous	I2	23
Iodide ion	Aqueous	I−	−55
Iron
Fe	Solid	Fe	0
Iron carbide (Cementite)	Solid	Fe3C	five.4
Iron(II) carbonate (Siderite)	Solid	FeCO3	−750.6
Iron(III) chloride	Solid	FeCl3	−399.4
Atomic number 26(II) oxide (Wüstite)	Solid	FeO	−272
Iron(2,III) oxide (Magnetite)	Solid	FethreeO4	−1118.4
Iron(Three) oxide (Hematite)	Solid	Atomic number 26iiO3	−824.2
Fe(2) sulfate	Solid	FeSOfour	−929
Atomic number 26(3) sulfate	Solid	Fetwo(Sofour)iii	−2583
Fe(II) sulfide	Solid	FeS	−102
Pyrite	Solid	FeS2	−178
Lead
Lead	Solid	Atomic number 82	0
Lead dioxide	Solid	PbOtwo	−277
Lead sulfide	Solid	PbS	−100
Lead sulfate	Solid	PbSO4	−920
Lead(Two) nitrate	Solid	Pb(NO3)2	−452
Lead(II) sulfate	Solid	PbSO4	−920
Lithium
Lithium fluoride	Solid	LiF	−616.93
Magnesium
Magnesium	Solid	Mg	0
Magnesium ion	Aqueous	Mg2+	−466.85
Magnesium carbonate	Solid	MgCO3	−1095.797
Magnesium chloride	Solid	MgCl2	−641.8
Magnesium hydroxide	Solid	Mg(OH)two	−924.54
Magnesium hydroxide	Aqueous	Mg(OH)2	−926.8
Magnesium oxide	Solid	MgO	−601.6
Magnesium sulfate	Solid	MgSO4	−1278.2
Manganese
Manganese	Solid	Mn	0
Manganese(Two) oxide	Solid	MnO	−384.nine
Manganese(Four) oxide	Solid	MnOii	−519.7
Manganese(3) oxide	Solid	Mn2Othree	−971
Manganese(2,III) oxide	Solid	Mn3O4	−1387
Permanganate	Aqueous	MnO − iv	−543
Mercury
Mercury(Two) oxide (red)	Solid	HgO	−90.83
Mercury sulfide (ruby-red, cinnabar)	Solid	HgS	−58.two
Nitrogen
Nitrogen	Gas	Ntwo	0
Ammonia (ammonium hydroxide)	Aqueous	NH3 (NH4OH)	−80.8
Ammonia	Gas	NH3	−46.1
Ammonium nitrate	Solid	NH4NO3	−365.half dozen
Ammonium chloride	Solid	NHfourCl	−314.55
Nitrogen dioxide	Gas	NO2	33.2
Hydrazine	Gas	N2Hfour	95.4
Hydrazine	Liquid	NorthiiHiv	50.half dozen
Nitrous oxide	Gas	NtwoO	82.05
Nitric oxide	Gas	NO	90.29
Dinitrogen tetroxide	Gas	NiiOiv	9.16
Dinitrogen pentoxide	Solid	N2O5	−43.1
Dinitrogen pentoxide	Gas	N2O5	11.3
Nitric acrid	Aqueous	HNO3	−207
Oxygen
Monatomic oxygen	Gas	O	249
Oxygen	Gas	O2	0
Ozone	Gas	Othree	143
Phosphorus
White phosphorus	Solid	Piv	0
Red phosphorus	Solid	P	−17.four[5]
Blackness phosphorus	Solid	P	−39.three[v]
Phosphorus trichloride	Liquid	PCl3	−319.7
Phosphorus trichloride	Gas	PCl3	−278
Phosphorus pentachloride	Solid	PClv	−440
Phosphorus pentachloride	Gas	PCl5	−321
Phosphorus pentoxide	Solid	P2O5	−1505.5[6]
Potassium
Potassium bromide	Solid	KBr	−392.two
Potassium carbonate	Solid	K2CO3	−1150
Potassium chlorate	Solid	KClOthree	−391.4
Potassium chloride	Solid	KCl	−436.68
Potassium fluoride	Solid	KF	−562.6
Potassium oxide	Solid	Grand2O	−363
Potassium nitrate	Solid	KNOiii	−494.5
Potassium perchlorate	Solid	KClO4	−430.12
Silicon
Silicon	Gas	Si	368.ii
Silicon carbide	Solid	SiC	−74.4,[7] −71.5[viii]
Silicon tetrachloride	Liquid	SiCl4	−640.ane
Silica (Quartz)	Solid	SiO2	−910.86
Argent
Argent bromide	Solid	AgBr	−99.5
Silver chloride	Solid	AgCl	−127.01
Silver iodide	Solid	AgI	−62.four
Silverish oxide	Solid	Ag2O	−31.1
Silvery sulfide	Solid	Ag2South	−31.eight
Sodium
Sodium	Solid	Na	0
Sodium	Gas	Na	107.five
Sodium bicarbonate	Solid	NaHCO3	−950.8
Sodium carbonate	Solid	Na2COthree	−1130.77
Sodium chloride	Aqueous	NaCl	−407.27
Sodium chloride	Solid	NaCl	−411.12
Sodium chloride	Liquid	NaCl	−385.92
Sodium chloride	Gas	NaCl	−181.42
Sodium chlorate	Solid	NaClO3	−365.4
Sodium fluoride	Solid	NaF	−569.0
Sodium hydroxide	Aqueous	NaOH	−469.15
Sodium hydroxide	Solid	NaOH	−425.93
Sodium hypochlorite	Solid	NaOCl	−347.1
Sodium nitrate	Aqueous	NaNO3	−446.2
Sodium nitrate	Solid	NaNOiii	−424.8
Sodium oxide	Solid	Na2O	−414.two
Sulfur
Sulfur (monoclinic)	Solid	Sviii	0.3
Sulfur (rhombic)	Solid	S8	0
Hydrogen sulfide	Gas	H2S	−twenty.63
Sulfur dioxide	Gas	So2	−296.84
Sulfur trioxide	Gas	So3	−395.seven
Sulfuric acid	Liquid	HiiSO4	−814
Tin can
Titanium
Titanium	Gas	Ti	468
Titanium tetrachloride	Gas	TiCl4	−763.ii
Titanium tetrachloride	Liquid	TiCl4	−804.2
Titanium dioxide	Solid	TiO2	−944.7
Zinc
Zinc	Gas	Zn	130.7
Zinc chloride	Solid	ZnClii	−415.1
Zinc oxide	Solid	ZnO	−348.0
Zinc sulfate	Solid	ZnSO4	−980.14

Aliphatic hydrocarbons [edit]

Formula	Name	Δf H ⦵ /(kcal/mol)	Δf H ⦵ /(kJ/mol)
Straight-concatenation
CHfour	Methane	−17.9	−74.9
CtwoHsix	Ethane	−xx.0	−83.seven
CiiHfour	Ethylene	12.5	52.v
C2Hii	Acetylene	54.2	226.viii
C3H8	Propane	−25.0	−104.6
C4H10	n-Butane	−30.0	−125.5
C5H12	due north-Pentane	−35.ane	−146.9
Chalf dozenHfourteen	n-Hexane	−forty.0	−167.4
CviiH16	due north-Heptane	−44.ix	−187.9
C8H18	due north-Octane	−49.8	−208.4
C9Htwenty	n-Nonane	−54.8	−229.3
CxH22	north-Decane	−59.vi	−249.4
C4 Alkane branched isomers
C4H10	Isobutane (methylpropane)	−32.i	−134.three
C5 Alkane branched isomers
C5H12	Neopentane (dimethylpropane)	−xl.1	−167.8
CfiveH12	Isopentane (methylbutane)	−36.9	−154.4
C6 Alkane series branched isomers
C6Hxiv	two,2-Dimethylbutane	−44.5	−186.2
Chalf-dozenHfourteen	two,iii-Dimethylbutane	−42.5	−177.8
C6H14	ii-Methylpentane (isohexane)	−41.8	−174.nine
C6H14	iii-Methylpentane	−41.1	−172.0
C7 Alkane branched isomers
C7H16	2,ii-Dimethylpentane	−49.2	−205.9
C7H16	2,ii,iii-Trimethylbutane	−49.0	−205.0
C7H16	3,3-Dimethylpentane	−48.1	−201.3
CviiH16	2,3-Dimethylpentane	−47.iii	−197.9
C7H16	2,4-Dimethylpentane	−48.ii	−201.seven
CviiH16	2-Methylhexane	−46.5	−194.six
C7H16	3-Methylhexane	−45.7	−191.2
C7H16	3-Ethylpentane	−45.3	−189.5
Cviii Alkane branched isomers
C8H18	2,three-Dimethylhexane	−55.1	−230.5
C8H18	2,2,3,iii-Tetramethylbutane	−53.nine	−225.5
C8H18	ii,two-Dimethylhexane	−53.7	−224.vii
C8H18	two,2,4-Trimethylpentane (isooctane)	−53.v	−223.eight
CviiiH18	two,five-Dimethylhexane	−53.two	−222.vi
CeightH18	2,ii,3-Trimethylpentane	−52.6	−220.ane
C8Hxviii	3,iii-Dimethylhexane	−52.vi	−220.1
CeightH18	2,iv-Dimethylhexane	−52.4	−219.2
C8Hxviii	2,three,4-Trimethylpentane	−51.9	−217.one
C8H18	two,iii,3-Trimethylpentane	−51.7	−216.3
C8H18	2-Methylheptane	−51.v	−215.five
C8H18	3-Ethyl-3-Methylpentane	−51.iv	−215.1
C8H18	3,4-Dimethylhexane	−50.9	−213.0
CviiiH18	3-Ethyl-2-Methylpentane	−fifty.4	−210.nine
C8H18	3-Methylheptane	−60.3	−252.v
CviiiH18	iv-Methylheptane	?	?
C8Heighteen	3-Ethylhexane	?	?
C9 Alkane series branched isomers (selected)
CnineH20	ii,2,4,4-Tetramethylpentane	−57.8	−241.8
C9Hxx	2,ii,3,3-Tetramethylpentane	−56.7	−237.2
CnineH20	2,ii,3,4-Tetramethylpentane	−56.six	−236.8
C9H20	2,3,3,4-Tetramethylpentane	−56.4	−236.0
CixH20	three,3-Diethylpentane	−55.7	−233.0

Other organic compounds [edit]

Species	Stage	Chemical formula	Δf H ⦵ /(kJ/mol)
Acetone	Liquid	CthreeHhalf-dozenO	−248.iv
Benzene	Liquid	Chalf dozenHvi	48.95
Benzoic acid	Solid	C7H6O2	−385.2
Carbon tetrachloride	Liquid	CCliv	−135.4
Carbon tetrachloride	Gas	CCl4	−95.98
Ethanol	Liquid	C2HfiveOH	−277.0
Ethanol	Gas	C2H5OH	−235.3
Glucose	Solid	CsixH12O6	−1271
Isopropanol	Gas	C3H7OH	−318.i
Methanol (methyl alcohol)	Liquid	CHthreeOH	−238.4
Methanol (methyl alcohol)	Gas	CH3OH	−201.0
Methyl linoleate (Biodiesel)	Gas	C19H34O2	−356.iii
Sucrose	Solid	C12H22O11	−2226.one
Trichloromethane (Chloroform)	Liquid	CHCl3	−134.47
Trichloromethane (Chloroform)	Gas	CHCl3	−103.18
Vinyl chloride	Solid	CiiH3Cl	−94.12

See as well [edit]

• Calorimetry
• Enthalpy
• Heat of combustion
• Thermochemistry

References [edit]

1. ^ IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Golden Book") (1997). Online corrected version: (2006–) "standard force per unit area". doi:ten.1351/goldbook.S05921
2. ^ Oxtoby, David West; Pat Gillis, H; Campion, Alan (2011). Principles of Modern Chemistry. p. 547. ISBN978-0-8400-4931-5.
3. ^ Moore, Stanitski, and Jurs. Chemistry: The Molecular Science. 3rd edition. 2008. ISBN 0-495-10521-X. pages 320–321.
4. ^ "Enthalpies of Reaction". world wide web.science.uwaterloo.ca. Archived from the original on 25 Oct 2017. Retrieved 2 May 2018.
5. ^ ^{a b} Housecroft, C. E.; Sharpe, A. K. (2004). Inorganic Chemistry (2nd ed.). Prentice Hall. p. 392. ISBN978-0-13-039913-seven.
6. ^ Green, D.W., ed. (2007). Perry's Chemical Engineers' Handbook (8th ed.). Mcgraw-Hill. p. 2–191. ISBN9780071422949.
7. ^ Kleykamp, H. (1998). "Gibbs Energy of Formation of SiC: A contribution to the Thermodynamic Stability of the Modifications". Berichte der Bunsengesellschaft für physikalische Chemie. 102 (nine): 1231–1234. doi:10.1002/bbpc.19981020928.
8. ^ "Silicon Carbide, Alpha (SiC)". March 1967. Retrieved 5 February 2019.

• Zumdahl, Steven (2009). Chemical Principles (sixth ed.). Boston. New York: Houghton Mifflin. pp. 384–387. ISBN978-0-547-19626-8.

External links [edit]

• NIST Chemistry WebBook

Enthalpy Of Formation Of Water,

Source: https://en.wikipedia.org/wiki/Standard_enthalpy_of_formation

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