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
34kurt
3 years ago
12

Consider the exothermic reaction

Chemistry
1 answer:
alisha [4.7K]3 years ago
4 0

Answer:

The answer to your question is -2855 J

Explanation:

Reaction

                     2C₂H₆  +  7O₂   ⇒   4CO₂  +  6H₂O

Formula

Heat of reaction = ΔHrxn = ΣΔHrxn products - ΣΔHrxn reactants

Substitution

ΔHrxn = { 4(-393.5) + 6(-241.8)} - {2(-84.7) + 7(0)}

ΔHrxn = {-1574 -1450.8} - {-169.4}

ΔHrxn = -3024.8 + 169.4

ΔHrxn = -2855.4 J

You might be interested in
The atomic masses of any two elements contain the same number of
den301095 [7]

Answer:

They contain of atoms

Explanation:

That's because atomic weights or masses of each atom of each element are proportional to each other, the same number of atoms of each element will give masses that are also proportional to each other. If you start with 20 oxygen atoms, you will need 40 hydrogen atoms to make the water and you will get 20 molecules of water.

8 0
3 years ago
What does multivalent mean???
salantis [7]
In the context of multivalent ions, it is when it has multiple oxidative states. 
4 0
3 years ago
A student weighs an empty flask and stopper and finds the mass to be 55.844 g. She then adds about 5 mL of an unknown liquid and
Oduvanchick [21]

Answer :

(a) The pressure of the vapor in the flask in atm is, 0.989 atm

(b) The temperature of the vapor in the flask in Kelvin is, 372.7 K

    The volume of the flask in liters is, 0.2481 L

(c) The mass of vapor present in the flask was, 0.257 g

(d) The number of moles of vapor present are 0.00802 mole.

(e) The mass of one mole of vapor is 32.0 g/mole

Explanation : Given,

Mass of empty flask and stopper = 55.844 g

Volume of liquid = 5 mL

Temperature = 99.7^oC

Mass of flask and condensed vapor = 56.101 g

Volume of flask = 248.1 mL

Barometric pressure in the laboratory = 752 mmHg

(a) First we have to determine the pressure of the vapor in the flask in atm.

Pressure of the vapor in the flask = Barometric pressure in the laboratory = 752 mmHg

Conversion used :

1atm=760mmHg

or,

1mmHg=\frac{1}{760}atm

As, 1mmHg=\frac{1}{760}atm

So, 752mmHg=\frac{752mmHg}{1mmHg}\times \frac{1}{760}atm=0.989atm

Thus, the pressure of the vapor in the flask in atm is, 0.989 atm

(b) Now we have to determine the temperature of the vapor in the flask in Kelvin.

Conversion used :

K=273+^oC

As, K=273+^oC

So, K=273+99.7=372.7

Thus, the temperature of the vapor in the flask in Kelvin is, 372.7 K

Now we have to determine the volume of the flask in liters.

Conversion used :

1 L = 1000 mL

or,

1 mL = 0.001 L

As, 1 mL = 0.001 L

So, 248.1 mL = 248.1 × 0.001 L = 0.2481 L

Thus, the volume of the flask in liters is, 0.2481 L

(c) Now we have to determine the mass of vapor that was present in the flask.

Mass of flask and condensed vapor = 56.101 g

Mass of empty flask and stopper = 55.844 g

Mass of vapor in flask = Mass of flask and condensed vapor - Mass of empty flask and stopper

Mass of vapor in flask = 56.101 g - 55.844 g

Mass of vapor in flask = 0.257 g

Thus, the mass of vapor present in the flask was, 0.257 g

(d) Now we have to determine the number of moles of vapor present.

Using ideal gas equation:

PV = nRT

where,

P = Pressure of vapor = 0.989 atm

V = Volume of vapor  = 0.2481 L

n = number of moles of vapor = ?

R = Gas constant = 0.0821 L.atm/mol.K

T = Temperature of vapor = 372.7 K

Putting values in above equation, we get:

(0.989atm)\times 0.2481L=n\times (0.0821L.atm/mol.K)\times 372.7K\\\\n=0.00802mole

Thus, the number of moles of vapor present are 0.00802 mole.

(e) Now we have to determine the mass of one mole of vapor.

\text{Mass of one mole of vapor}=\frac{\text{Mass of vapor}}{\text{Moles of vapor}}

\text{Mass of one mole of vapor}=\frac{0.257g}{0.00802mole}=32.0g/mole

Thus, the mass of one mole of vapor is 32.0 g/mole

8 0
3 years ago
Which of the following phrases best describes a synthesis reaction?
iogann1982 [59]
Answer is D breaking apart I to not more than two
4 0
3 years ago
What is the electron configuration of aluminum?
Bond [772]
 <span>What is the electron configuration of aluminum is </span>1s^2 2s^2 2p^6 3s^2 3p^1.
8 0
3 years ago
Other questions:
  • Why should carbonated beverages be kept cold?
    8·1 answer
  • Na (atomic no. 11) reacts with Cl (atomic no. 17) to become stable. In the reaction, Na will ____________, while Cl will _______
    7·1 answer
  • Significant digits are the number of digits that reflect the precision of a measurement or number. true or false
    14·1 answer
  • What element is not classified as a metal, nonmetal, or metalloid?​
    14·1 answer
  • Determine the molar mass of CuSO4×5H2O
    5·1 answer
  • Name the precipitate that forms when aqueous solutions of barium nitrate and potassium sulfate are mixed.
    7·1 answer
  • Gasoline is a product of crude oil, compressed organic matter formed from accumulations of algae millions of years ago. Some pla
    14·1 answer
  • Answer the two questions by using the pictures, thanks!
    15·1 answer
  • Can anyone do this. i dont get it​
    8·1 answer
  • Which is one way that scientists ensure that data is reliable?
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!