The standard enthalpies of formation of gaseous propyne, propylene, and propane are +185.4, +20.4, and -103.6 KJ/mol, respectively.Calculate the heat evolved per mole on combustion of each substance to yield CO2 and water.Calculate the heat evolved on combustion of 1 kg of each substance.Which is the most efficient fuel in terms of heat evolved per unit mass?

Question
Asked Dec 27, 2019
43 views
  • The standard enthalpies of formation of gaseous propyne, propylene, and propane are +185.4, +20.4, and -103.6 KJ/mol, respectively.
  1. Calculate the heat evolved per mole on combustion of each substance to yield CO2 and water.
  2. Calculate the heat evolved on combustion of 1 kg of each substance.
  3. Which is the most efficient fuel in terms of heat evolved per unit mass?
check_circle

Expert Answer

Step 1

Combustion reaction of propyne is given below.

C3H4 + 4 O2 ---> 3 CO2 + 2 H2O

Combustion reaction of propylene is given below.

C3H6 + 9/2 O2 ---> 3 CO2 + 3 H2O

Combustion reaction of propane is given below.

 C3H8 + 5 O2 ---> 3 CO2 + 4 H2O

Enthalpy of formation of H2O (l) = -241.818 kJ/mol

Enthalpy of formation of CO2 (g) = -393.509 kJ/mol

Enthalpy of formation of O2 (g) = 0 kJ/mol

Enthalpy of formation of propyne = 185.4 kJ/mol

Enthalpy of formation of propylene = 20.4 kJ/mol

Enthalpy of formation of propane = -103.6 kJ/mol

Enthalpy of reaction can be calculated as follows,

Chemistry homework question answer, step 1, image 1
fullscreen
Step 2
  1. Enthalpy of combustion for propyne, propylene and pr...
Chemistry homework question answer, step 2, image 1
fullscreen

Want to see the full answer?

See Solution

Check out a sample Q&A here.

Want to see this answer and more?

Solutions are written by subject experts who are available 24/7. Questions are typically answered within 1 hour.*

See Solution
*Response times may vary by subject and question.
Tagged in

Science

Chemistry

Related Chemistry Q&A

Find answers to questions asked by student like you
Show more Q&A
add
question_answer

Q: what are coinage metals?

A: Coinage metals are group of three transition metals of group 11 of periodic table.  The coinage meta...

question_answer

Q: what are anomalous behaviour of nitrogen?

A: N anomalous behavior are discussed as follows,Due to smaller size N differ from its group members by...

question_answer

Q: Draw structures that t each description and name the functional group in each molecule: (a) two cons...

A: Isomers have same molecular formula but differ in arrangement of atoms within a molecule.Constitutio...

question_answer

Q: copper can be extracted by hydrometallurgy but not zinc. explain.

A: The reduction potential of Zinc is lower than that of copper. In hydrometallurgy, in order to displa...

question_answer

Q: explain the mechanism of cleansing action of soap.

A: Soap consists of hydrocarbon tail and head in which tail is hydrophobic (water repelling) and head i...

question_answer

Q: What two enols are formed when pent-2-yne is treated with H2O, H2SO4, and HgSO4? Draw the ketones fo...

A: In the presence of HgSO4 and H2SO4, alkynes undergo hydration and produces an enol as a product. The...

question_answer

Q: What do you mean by decarboxylation?

A: Given,Decarboxylation reaction

question_answer

Q: Reaction of pentanoyl chloride (CH3CH2CH2CH2COCl) with lithium dimethyl cuprate [LiCu(CH3)2] forms a...

A: The reaction of pentanoyl chloride (CH3CH2CH2CH2COCl) with lithium dimethyl cuprate [LiCu(CH3)2] for...

question_answer

Q: Under certain reaction conditions, 2,3-dibromobutane reacts with two equivalents of base to give thr...

A: The structure of 2,3-dibromobutane can be written as