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
ohaa [14]
3 years ago
9

The heat of reaction for the combustion of propane is –2,045 kJ. This reaction is: C3H8(g) +502 (g) 3CO2 (g) + 4H2O (g). Determi

ne the standard heat of formation of propane.
Chemistry
1 answer:
Ede4ka [16]3 years ago
8 0

Answer:

\Delta _fH_{C_3H_8}=-102.7kJ/mol

Explanation:

Hello,

In this case, we can consider that the given heat of combustion is indeed the heat of reaction since it corresponds to the combustion of propane, which is computed by using the heat formation of all the involved species as shown below:

\Delta _cH=3*\Delta _fH_{CO_2}+4*\Delta _fH_{H_2O}-\Delta _fH_{C_3H_8}-5*\Delta _fH_{O_2}

Thus, since the heat of formation of gaseous carbon dioxide is -393.5 kJ/mol, water -241.8 kJ/mol and oxygen 0 kJ/mol, the heat of formation of propane is:

\Delta _fH_{C_3H_8}=3*\Delta _fH_{CO_2}+4*\Delta _fH_{H_2O}-5*\Delta _fH_{O_2}-\Delta _cH\\\\\Delta _fH_{C_3H_8}=3*(-393.5)+4*(-241.8)-5*0-(-2045)\\\\\Delta _fH_{C_3H_8}=-102.7kJ/mol

Best regards.

You might be interested in
The mass of a 50-mL volumetric flask is 40.638 g. After adding 15.0 mL of 95% ethanol and adding enough water to complete the vo
Nuetrik [128]

Answer

0.9516 grams / mL (50.00 has 4 sig digs.)

Remark

You have a couple of extraneous numbers there. You don't care about anything except the mass of the flask +  water/alcohol mixture  (88.219 grams). and the mass of the flask (40.638 grams)

Formulas

  • mass water/alcohol mixture = mass of the flask with fluid - mass flask
  • density = mass / volume

Solution

mass water/alcohol mixture = 88.219 - 40.638 = 47.581

  • Volume = 50 mL
  • Density = mass / Volume
  • Density = 47.581/50
  • Density = 0.95162  There are 4 sig digs so the answer should be
  • 0.9516
3 0
3 years ago
Water carries helpful nutrients to new areas,
den301095 [7]

Answer:

Positive Flood I believe

8 0
3 years ago
Read 2 more answers
When should you<br> use a fume hood?
AfilCa [17]

Answer:

if you are working with hazardous materials.

Explanation:

A properly operating and correctly used fume hood can reduce or eliminate exposure to volatile liquids, dusts, and mists. It is advisable to use a laboratory hood when working with all hazardous substances.

4 0
3 years ago
What is the formula of copper sulphate?​
mylen [45]

COPPER SULPHATE =CuSO4

4 0
3 years ago
Read 2 more answers
en un recipiente se tiene 800 g de una solución al 35% en masa de ácido sulfuroso, de la cual se evapora 80ml de agua. ¿cuál es
Alinara [238K]

The mass percent of sulfurous acid in the new solution : 38.9%

<h3>Further explanation</h3>

<em>In a container you have 800 g of a 35% by mass solution of sulfurous acid, from which 80 ml of water evaporates. What is the mass percent of sulfurous acid in the new solution? data: density of water is 1g / ml.</em>

<em />

solution 1

composition :

  • 35% acid :

\tt 0.35\times 800~g=280~g

  • water :

\tt 800-280=520~g

solution 2(new solution)

composition :

  • water

\tt 520-(80~ml\times 1~g/ml)=440~g

  • Total mass of new solution after water evaporated

\tt 280(acid)+440(water)=720~g

  • %mass of acid in a new solution

\tt \dfrac{280}{720}\times 100\%=38.9\%

5 0
2 years ago
Other questions:
  • Saltpeter is a compound made of potassium(K), nitrogen(N), and oxygen(O). Every 100.0g of saltpeter contains 38.67g potassium an
    14·1 answer
  • The molar concentration (M) of a solution prepared by dissolving 0.2362g of Cr(NO3)3 in a 50-mL volumetric flask is 0.01985M, wh
    13·1 answer
  • What is the chemical formula for the binary compound composed of al3+ and o2- ions?
    13·1 answer
  • 6. A 25.0-mL sample of 0.125 M pyridine is titrated with 0.100 M HCI. Calculate the pH
    7·1 answer
  • Draw the product or products that are obtained from the reaction of HCl with 1-butene and with 2-butene. Show the relative stere
    14·1 answer
  • Please help with Chem I DON'T HAVE ENOUGH TIME!
    15·2 answers
  • TRUE OR FALSE: Chromosomes are made up of proteins joined together like beads on a string.
    8·2 answers
  • Use the chemical equation and the bond diagram to answer the question.
    15·1 answer
  • How many protons, neutrons, and electrons in Cl-?
    8·1 answer
  • How many 325 mg aspirin tablets can be made from 875 g of aspirin?
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!