Which of the following have a standard enthalpy of formation (ΔHf°) equal to zero?
Which of the following substances has a standard enthalpy of formation (ΔHf°) equal to zero?
1) F2(g)
2) Hg(l)
3) NH3(g)
4) C(diamond)
2 Answers
F2(g) and Hg(l) have a standard enthalpy of formation (ΔHf°) equal to zero.
They are elemental and in their standard state.
~~~~
NH3 is not elemental and it has a nonzero enthalpy of formation.
C(s, diamond) is not the standard state of carbon. Diamond has a nonzero enthalpy of formation.
(Solid graphite is the standard state of carbon, and hence has a standard enthalpy of formation equal to zero.)
Dec 27, 2024
All elements in in standard state (298 kelvin and 1atm) have the standard enthalpy of formation equal to zero. Therefore diamond is the answer.
Related Questions
How many oxygen atoms are in 2.00 grams of quartz? Could someone please provide a detailed explanation of the calculatio...
How many moles of CO2 are produced when 5.45 moles of ethane (C2H6) are burned in an excess of oxygen?
Suppose there are two known compounds containing the elements x and y, and you have a 1.00 g sample of each compound. Wh...
What is the hybridization of the phosphorus atom in PCl3? Additionally, could you please provide an explanation of the s...
¿Cuál es la tendencia de los metales al formar enlaces? ¿Qué rango de edad sería el adecuado para explicar esta respuest...
How many moles of copper (Cu) are present in 1.48 × 10²⁵ atoms of copper?
Together, leukocytes and platelets comprise approximately a certain percentage of total blood volume. In biological ter...
What is the hybridization of the central atom in the molecules CH2F2 (difluoromethane) and COF2 (carbonyl fluoride)? Add...
What is the speed of light in kilometers per hour?
What are the steps to create an energy level diagram for aluminum? Could you provide detailed guidance on how to accurat...