1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Ganezh [65]
3 years ago
9

Estimate the enthalpy change for the combustion of one mole of acetylene, C2H2, to form carbon dioxide and water vapor. BE(C?H)

= 456 kJ/mol) BE(C?C) = 962 kJ/mol BE(O=O) = 499 kJ/mol BE(C=O) = 802 kJ/mol BE(O?H) = 462 kJ/molAnswer choices:A. +653 kJ/molB. ?155 kJ/molC. +1010 kJ/molD. ?1759 kJ/molE. ?1010 kJ/mol
Chemistry
1 answer:
tia_tia [17]3 years ago
4 0

Answer:

ΔH rxn =  -1010 kJ/molC₂H₂

Explanation:

To obtain the enthalpy change for a reaction from bond energies what we do is to make an inventory of the bonds broken and formed for the balanced chemical reaction:

C₂H₂ + 5/2O₂   ⇒   2CO₂ + H₂O

Bond Broken                                    Bonds Formed

2 C-H + 1 C≡C + 5/2 O=O                4C=O + 2 H-O

Enthalpy bonds broken:

2 mol (456 kJ/mol)+ 1 mol (962 kJ/mol) + 5/2 mol (499 kJ/mol)  =  3121.5 kJ

Enthalpy bond formed:

4 mol (802 kJ/mol) + 2 mol (462 kJ/mol) = 4132.0 kJ

ΔH rxn = H broken - H formed =  3121.5 kJ - 4132.0 kJ = - 1010  kJ (per mol C₂H₂ )

You might be interested in
Which phrase describes a hypothesis? a. reviewing information related to the problem b. testing a factor, or variable, in an exp
monitta

Answer:

c. suggesting a solution to a problem after studying it carefully

Explanation:

Hypothesis generally refers to an assumption made. This assumption can either be true or false. It is a reasoning presented in order to explain a phenomenon and is the starting point for further investigation.

Among the options, the closest that best describes it is option C.

4 0
3 years ago
How is thermal energy transferred between two objects that are at different temperatures?
qwelly [4]

Answer:

heat flows from the object that has more thermal more energy to the object with less thermal energy

8 0
3 years ago
Write molecular, complete ionic, and net ionic equations for the reactions that occur, if any, when solutions of the following s
Gnom [1K]
<span>The molecular formula that describes the problem is
2CH3COOH (aq) + Ca(OH)2 (s) ---> Ca(CH3COO)2 (aq) + 2H2O (l)

The net equation is written as follows:
2CH3COOH- (aq) + 2H+ (aq) + Ca(OH)2 (s) ---> Ca2+ (aq) + 2 CH3COO- (aq) + 2H2O (l)
canceling out spectator ions
2H+ (aq) + Ca(OH)2 (s) ---> Ca2+ (aq) + 2 H2O (l)</span>
4 0
3 years ago
Estimate the air pressure at an altitude of 5km
r-ruslan [8.4K]
The answer is 100 kg
6 0
3 years ago
Explain what makes insulative materials work most effectively.
KengaRu [80]

Answer:

Most common insulation materials work by slowing conductive heat flow and--to a lesser extent--convective heat flow. Radiant barriers and reflective insulation systems work by reducing radiant heat gain. To be effective, the reflective surface must face an air space.

Explanation:

To be effective, the reflective surface must face an air space.

6 0
3 years ago
Other questions:
  • Which will not appear in the equilibrium constant expression for the reaction below
    13·2 answers
  • How many milliliters of 1.50 m hcl(aq) are required to react with 5.45 g of an ore containing 32.0% zn(s) by mass?
    6·1 answer
  • 1. Radioactive decay of 40K atoms in an igneous rock has resulted in a ratio of 25 percent 40K atoms to 75 percent 40Ar and 40Ca
    6·1 answer
  • What is a cool 1 week or less science fair project for grade 9?
    13·2 answers
  • ) Each of the following is a noncovalent interaction EXCEPT: A) a hydrogen bond. B) a carbon-hydrogen bond. C) the interaction b
    12·1 answer
  • Convert a pressure of 0.0248 mm Hg to the equivalent pressure in pascals (Pa).
    9·1 answer
  • Why are different units of measurement used for distances in space
    5·1 answer
  • A mixture of BaCl2 and NaCl is analyzed by precipitating all the barium as BaSO4. After addition of an excess of Na2SO4 to a 3.6
    14·1 answer
  • How to can teste ion in salt​
    13·1 answer
  • How many atoms in total are there in 7.35 mol of magnesium oxide (MgO)<br> molecules?
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!