Which of the following chemical equations corresponds to the standard molar enthalpy of formation (ΔH°f) for Rb2SeO4?
2 Rb(s) + Se (s) + 2 O2(g) → Rb2SeO4 (s) |
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2 Rb(s) + Se(s) + 4 O(g) → Rb2SeO4 (s) |
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2 Rb+(aq) + SeO42-(aq) → Rb2SeO4 (s) |
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2 Rb+(aq) + SeO42-(aq) → Rb2SeO4 (aq) |
Which of the following chemical equations corresponds to the standard molar enthalpy of formation (ΔH°f) for...
The standard heat of formation, ΔH∘f, is defined as the enthalpy change for the formation of one mole of substance from its constituent elements in their standard states. Thus, elements in their standard states have ΔH∘f=0. Heat of formation values can be used to calculate the enthalpy change of any reaction. Consider, for example, the reaction 2NO(g)+O2(g)⇌2NO2(g) with heat of formation values given by the following table: Substance ΔH∘f (kJ/mol) NO(g) 90.2 O2(g) 0 NO2(g) 33.2 Then the standard heat...
The standard enthalpy of formation (ΔH∘f) is the enthalpy change that occurs when exactly 1 mol of a compound is formed from its constituent elements under standard conditions. The standard conditions are 1 atm pressure, a temperature of 25 ∘C , and all the species present at a concentration of 1 M . A "standard enthalpies of formation table" containing ΔH∘f values might look something like this: Substance ΔH∘f H(g) 218 kJ/mol H2(g) 0 kJ/mol Ba(s) 0 kJ/mol Ba2+(aq) −538.4...
Write a balanced chemical equation that corresponds to the standard molar enthalpy of formation of Na_2CO_3(s)?
Which of the following reactions corresponds to the thermochemical equation for the standard molar enthalpy of formation of solid zinc nitrate? a. Zn(s) + 2N(g) + 6O(g) → Zn(NO3)2(s) b. Zn(s) + 2HNO3(aq) → Zn(NO3)2(s) + H2(g) c. Zn(OH)2(s) + 2HNO3(aq) → Zn(NO3)2(s) + 2H2O() d. Zn2+(aq) + 2NO3–(aq) → Zn(NO3)2(s) e. Zn(s) + N2(g) + 3O2(g) → Zn(NO3)2(s)
Calculate the standard enthalpy change, ΔH°rxn, in kJ for the following chemical equation, using only the thermochemical equations below: CaCO3(s) → CaO(s) + CO2(g) Report your answer to three significant figures in scientific notation. Equations: ΔH°rxn (kJ) Ca(s) + CO2(g) + 1/2O2(g) → CaCO3(s) -812.5 2Ca(s) + O2(g) → 2CaO(s) -1270.3
Write the chemical equation for the reaction whose enthalpy change is the standard enthalpy of formation of raffinose, C18H32O16(s), ΔH∘f[C18H32O16]. Express your answer as a chemical equation. Identify all of the phases in your answer.
Write the chemical equation for the reaction whose enthalpy change is the standard enthalpy of formation of raffinose, C18H32O16(s), ΔH∘f[C18H32O16]. Express your answer as a chemical equation. Identify all of the phases in your answer.
What is the standard enthalpy of formation of What is the standard enthalpy of formation of CH 3 CH 2 CH 2 CHO(l)? CH3CH2CH2CHO(l)? 2CH 3 CH 2 CH 2 CHO(l)+5O 2 (g)→8H 2 O(l)+8CO 2 (g); 2CH3CH2CH2CHO(l)+5O2(g)→8H2O(l)+8CO2(g); ΔH°=–4943.6 kJ ΔH°=–4943.6 kJ Substance ΔH° f (kJ/mol) CO 2 (g) -393.5 H 2 O(l) –285.8 a. –245.4 kJ/mol b. +245.4 kJ/mol c. –1792.5 kJ/mol d. –3151.1 kJ/mol e. +3151.1 kJ/mol
Part A) What is ΔH∘rxn for the following chemical reaction? CO2(g)+2KOH(s)→H2O(g)+K2CO3(s) You can use the following table of standard heats of formation (ΔH∘f) to calculate the enthalpy of the given reaction. Element/ Compound Standard Heat of Formation (kJ/mol) Element/ Compound Standard Heat of Formation (kJ/mol) H(g) 218 N(g) 473 H2(g) 0 O2(g) 0 KOH(s) −424.7 O(g) 249 CO2(g) −393.5 K2CO3(s) −1150kJ C(g) 71 H2O(g) −241.8kJ C(s) 0 HNO3(aq) −206.6 Express the standard enthalpy of reaction to three significant figures and...
Calculate the standard enthalpy change, ΔH, for the formation of 1 mol of strontium carbonate (the material that gives the red color in fireworks) from its elements. Sr(s) + C(graphite) + 32 O2(g) -----> SrCO3(s) The information available is: (1) Sr(s)+ 12O2(g) ---->SrO(s) DeltaH= -592kj (2) SrO(s) + CO2(g) -----> SrCO3(s) DeltaH= -234kj (3) C(graphite) + O2 (g) ----->CO2 (g) DeltaH= -394kl