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
Aliun [14]
3 years ago
13

A)

Chemistry
1 answer:
jeka57 [31]3 years ago
4 0

Answer:

Explanation:

a )

From the graph given , energy of reactant = 0

b )

energy of product = -15 kJ

c )

ΔH =   energy of product - energy of reactant

= -15 - 0  = - 15 kJ

ΔH is negative  so reaction is exothermic .

d ) Activation energy = 25 - 0 = 25 kJ .

e ) Energy released = 15 kJ .

You might be interested in
What is paper chromatography? Calculate the Rr value of a colored dye that traveled 52 mm on a chromatography strip while the so
Karo-lina-s [1.5K]

Answer:

Paper chromatography is a basic technique of chromatography. It consist in the separation of the mixe components using a solvent.

Explanation:

Paper chromatography is a basic technique of chromatography. It consists in the separation of the mixed components using a solvent.

Paper chromatography consists of put some dot of the mix using a glass capillary into a specialized paper, generally made of cellulose, this is called a stationary phase.

Then you put this paper into a camera of glass named, chromatography camera, where previously contain a solvent. The solvent also know as a mobile phase, the type can be defined before the test and involves a study of the kind of the mix, and the compound you want to separate.

The chromatography camera has to be closed all the time during the test, and you can't move at all because the movement of the solvent can alternate the result.

Very often, the solution of the solvent is a mix of different liquid substances with different polarities.

When the stationary phase put into the camera, the solvent starts to move up over the paper, until the separation of the compounds is observable.

the Rf is a value who relates the move of the mobile phase with the move of the distance traveled by the substance tested.

To undersant the paper chromatography, you can watch the images attached.

The first is an image of the chromatography camera.

The second one is an image of a cellulose paper after the chromatography is done. You can watch the dots who indicates the traveling of the compound across the paper.

The third one can show you the evolutions of paper chromatography, from the beginning to the end.

To calculate the Rf value you have to use the equation:

Rf = distance traveled by the substance/distance traveled by the solvent/

<u>Rf = 52mm/81mm =0.64</u>

<u></u>

3 0
3 years ago
Design an invitation you could use to calculate the density of a penny
Nataliya [291]
Firstly, the density of any substance is represented by the mass (amount of matter) as divided by the volume(amount of space). According to external websites, the mass of a penny is 2.5 grams.However, the volume of a penny is .35cm to the power of 3 (due to the thickness of the penny being extremely minimal.Thus the amount of density is extremely little). Therefore, the density of a penny is 0.875 g/cm cubed (dimensional analysis).As for an invention that could be used, that is possible with the usage of a series of measurements that can both calculate mass and volume and directly allocate that to attain density
7 0
3 years ago
I need help please WOTH this
barxatty [35]

Answer:

Kenma I'll help you! it's B.

Explanation:

I hope I helped you Kenma

7 0
3 years ago
Approximately how many particles are in 2 moles?
schepotkina [342]

Answer:

1.2\times10^2^4 particles in 2 moles.

Explanation:

The number of particles that are contained in one mole, the international unit of amount of substance: by definition, exactly 6.022×10²³, and it is dimensionless. It is named after the scientist Amedeo Avogadro.

It is also known as Avogadro's constant.

∴ Number of particles in one mole = 6.022\times10^2^3

∴ Number of particles in 2 mole = 2 times Number of particles in one mole

∴ Number of particles in 2 mole=2\times6.022\times10^2^3=12.044\times10^2^3\approx1.2\times10^2^4

Hence there are 1.2\times10^2^4 particles in 2 moles.

4 0
3 years ago
Read 2 more answers
Which of the following characteristics of the pineal gland is not correct? A. The pineal gland is located in the brain, above th
Marina CMI [18]

Answer:

D

Explanation:

The pineal gland regulates salt and water levels.

4 0
3 years ago
Other questions:
  • Two electrons are found in the same atom. One has the quantum number set (3, 2, 0, +?), and the other has the quantum number set
    10·1 answer
  • Drag the tiles to the boxes to form correct pairs.
    6·2 answers
  • How many moles of each substance are needed to prepare the following solutions?
    12·1 answer
  • What changes could be made to optimize the manufacturing process
    15·1 answer
  • The following reaction was carried out in a 3.25 L reaction vessel at 1100 K:
    10·1 answer
  • 1) Your nephew rides a kiddy train at the local carnival. The train, which has
    8·1 answer
  • Help its due soon i need to get this right to pass the class
    6·2 answers
  • Round off 1.732 kg to three significant figures. Express your answer with the appropriate units, Value and Units.
    6·1 answer
  • when an animal behaviorist attempts to explain or interpret her observations, she is_______. a. classifying her data b.making an
    6·1 answer
  • Which isoelectronic series is correctly arranged in order of increasing radius?.
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!