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2 years ago

What’s properties my change during a chemical reaction

Chemistry

1 answer:

sweet-ann [11.9K]2 years ago

7 0

Answer:

The signs of chemical change include changes in color, temperature, the production of light, changes in odor, and the formation of gases.

You might be interested in

What is Proportional to the energy of electromagnetic wave

padilas [110]

Answer:

The frequency

Step-by-step explanation:

The formula for the energy of an electromagnetic wave is

E = hf Thus,

E ∝ f and

f ∝ E

7 0

3 years ago

The pyrolysis of ethane proceeds with an activation energy of about 300 kJ/mol. How much faster is the decomposition at 625°C th

Alona [7]

Answer:

The decomposition of ethane is 153.344 times much faster at 625°C than at 525°C.

Explanation:

According to the Arrhenius equation,

$K=A\times e^{\frac{-Ea}{RT}}$

$\log (\frac{K_2}{K_1})=\frac{Ea}{2.303\times R}[\frac{1}{T_1}-\frac{1}{T_2}]$

where,

$K_2$ = rate of reaction at $T_2$

$K_1$ = rate of reaction at $T_1$

$Ea$ = activation energy of the reaction

R = gas constant = 8.314 J/K mol

$E_a=300 kJ/mol=300,000 J/mol$

$T_2=625^oC=898.15 K,T_1=525^oC=798.15 K$

$\log (\frac{K_2}{K_1})=\frac{300,000 J/mol}{2.303\times 8.314 J/K mol}[\frac{1}{798.15 K}-\frac{1}{898.15 K}]$

$\log (\frac{K_2}{K_1})=2.185666$

$K_2=153.344\times K_1$

The decomposition of ethane is 153.344 times much faster at 625°C than at 525°C.

4 0

3 years ago

Identify the molecular shape of each Lewis structure.

saw5 [17]

Panel One

Trigonal Planar: This is in the shape of a triangle. It is an equilateral triangle with three equal atoms/ions at each corner of the triangle. The most well known example is a molecule with Boron at the center and the corner molecules some like Florine or iodine.

Trigonal Planar is the second Lewis Diagram from the right.

The uploaded picture is the second from the left.

==========

Tetrahedral (Second Lewis Diagram from the left) is something like a pyramid except that that the base is triangular as are each of the faces. The carbon is in the center and the chlorines (in this example) are each in a corner. If this made of just carbon (like diamond or anthracite coal) then you are talking about something that is extremely hard. It's the first upload on the left.

=====================

The Trigonal pyramid is the first Lewis Diagram on the left. It usually has an unattached pair of electrons. Nitrogen or Phosphorous are ususally the samples in the center. The nitrogen with its unused paired electrons are at the peak of blue sphere in the diagram that is uploaded second from the right.

======================

The Bent one is first lewis diagram on the right. It bends because of the unbalance (and double bonds) away from the nitrogen. Water looks something like that. Water is an example of Bent.

The upload is first on the right. These diagrams help you visulize what the various molecules look like

Summary of Lewis Diagrams.

From Left to right on the diagrams you gave me.

Trigonal Pyramidal

Tetrahedral

Trigonal Planar

Bent

Summary of uploaded diagrams.

From Left to right

Tetrahedral

Trigonal Planar

Trigonal Pyramidal

Bent

Problem Two

The very quick answer is E. Water is a bent molecule. It is flat. It has a very definite (+) end and a very definite (-) end. The marriage of a plus end with a minus is a very long lasting relationship. It is not the strongest bond in the world, but it is strong enough to create all the properties that the stem of the question has listed. [High melting and boiling points and high surface tension.

A is a repulsive condition. Likes repulse. Wrong answer.

B is wrong. We are talking about water itself, not water with something in it.

C is Wrong. Water molecules are distinct. They are a bit on the hermit side. They do not connect directly with each other.

D Wrong. There is no interchange of electrons between molecules.