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A machine is a device that creates energy


FALSE!
We can't create or destroy energy. Machine is a device that converts one form of energy into another.

Hope this helps!

Related Questions

Posted in Chemistry

Which of the following statements about the use of nuclear energy is true? a. Nuclear energy cannot be used safely. b. Nuclear fusion has no known useful applications. c. Nuclear fission is currently more useful for producing energy than nuclear fusion. d. Nuclear fusion has fewer safety risks than nuclear fission.

Answer: The correct answer is "Nuclear energy cannot be used safely".

Explanation:

There are two types of nuclear reactions: Nuclear fission and Nuclear fusion.

Nuclear fission: The nuclear energy is originated from the splitting of uranium atom. Uranium is a radioactive material.

Nuclear reactor controls the release of energy.

The by product of the nuclear generation is the radioactive waste in the nuclear power plant.

The radioactive material emits harmful radiation. If there is any leakage in the power plant. Then, it would lead to hazard. It would harmful for the health of the employees who are working there.

Therefore, the correct option is (a).

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Which subatomic particle contains the energy stored in chemical bonds

Pretty sure that the energy stored in chemical bonds is ATP, so probably the mitochondria? idk if thats what you are asking

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Since most sources of noise pollution are caused by essential machines, it is not possible to decrease the levels of sound. True False

It would be false. 

You can do things to protect your hearing, e.g. wearing headphones or earplugs if you have to, or leaving the premises if the noise is becoming unbearable or painful. I often have to do this especially because I'm more sensitive to sounds than others, while sometimes you can't decrease the noise you can still protect yourself and your hearing. I hope this was helpful! :) 

Posted in Chemistry

Which is the best example of how electromagnetic energy is used in everyday life

Thank you for posting your question here at brainly. I hope the answer will help you. Feel free to ask more questions.

The best example of how electromagnetic energy is used in everyday life is a patient receiving an X-ray in a hospital

Posted in Chemistry

Atomic Number, Ionic Radius, and First Ionization Energy help! "Why do these relationships exist? Propose an explanation for each of these relationships." and "Are these relationships consistent with the periodic trends that you have been studying?"

The answer 

Why do these relationships exist?: The higher the atomic number of an element means the atomic radii will be bigger because there are more electrons and shells/orbitals involved which will make the element bigger in size. The more electrons there are means the more shells there are which equals to a bigger atomic radii. The first energisation energy will be lower the bigger the atomic number because a larger atomic number means more electrons. This means more shells and the electrons will be further away from the nucleus which equals to less nuclear attraction. This means as the electrons get further away from the nucleus (from the larger amount of electrons and more shells and shielding from the shells closer to the nucleus) there will be less attraction holding the electrons to the nucleus which will make it easier to remove. I'm not sure what the next question means, but I hope this helps explain why the relationships exist :)

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Which stage in the free radical substitution of methane by chlorine will have the lowest activation energy? A CH3• + Cl 2 → CH3Cl + Cl • B Cl • + Cl • → Cl 2 C Cl • + CH4 → CH3• + HCl D Cl 2 → Cl • + Cl •

I am pretty sure that the stage in the free radical substitution of methane by chlorine which will have the lowest activation energy is B Cl • + Cl • → Cl 2. I choose this option because during termination there is no breaking of bonds within two reactive  radicals which are joined together.

Do hope it will help you!


Posted in Chemistry

If you are asked to compare matter in solid, liquid, and gaseous states, which statement best defines a gas? highest energy, highest molecular motion, and least dense packaging of molecules highest energy, highest molecular motion, and most dense packaging of molecules least energy, highest molecular motion, and least dense packaging of molecules highest energy, least molecular motion, and least dense packaging of molecules

I am pretty sure that If I were asked to compare matter in solid, liquid, and gaseous states, the statement which would best defined a gas is highest energy, highest molecular motion, and least dense packaging of molecules. I choose this one because it's not sensible to heat CO2 (in case of safety) and in the last option the amount of energy is not satisfying.

Hope it helps!

Posted in Chemistry

For a hydrogen-like atom, classify these electron transitions by whether they result in the absorption or emission of light: n=3 to n=5, n=1 to n=3, n=3 to n=2, n=2 to n=1? Ignoring the sign, which transition was associated with the greatest energy change?

The problem ask to provide among the following transition that states the where the transition is absorption or a emission and the answer are the following:
1 absorption
2 absorption
3 emission
4 emission

Posted in Chemistry

1. A substance, A₂B, has the composition by mass of 60% A and 40% B. What is the composition of AB₂ by mass? 2. Draw a reaction profile for reaction 2N2+O2+heat→2N2O, must include proper labels for each axis, reactants, products, indication for activation energy and transition state.

This may help you
Use an arbitrary mass, 100 g is an easy number to work with. 60% of 100 g is 60 g, there are two A's. Each A is 30 g 40 g is B, and there is only one, so B is 40 g. AB2, would have a mass of 30 g + 2*40 g = 110 g The new percent by mass composition of A is: 30g110g∗100%=27.3% The new percent by mass composition of B is: 80g110g∗100%=72.7%

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Which chemical process is associated with the lattice energy for sodium chloride? NaCl(g) → Na+(g) + Cl-(g) NaCl(s) + H2O(l) → Na+(aq) + Cl-(aq) Na(s) + 1/2 Cl2(g) → NaCl(s) NaCl(s) → Na+(g) + Cl-(g)

I am absolutely sure thathe chemical process which is associated with the lattice energy for sodium chloride is the last option from the scale represented above - NaCl(s) → Na+(g) + Cl-(g). I choose this one because it has to perform reversed process that must release the same energy. 
Do hope you still need the answer because this one is really helpful!

Posted in Chemistry

Identify two places in the krebs cycle where a decrease in free energy is coupled with an increase

Cellular respiration is the process of breaking down food such as glucose into carbon dioxide and oxygen. During the process, cellular respiration also releases energy in the form of ATP (adenosine triphosphate) for use by all energy consuming activities of the cell. It is found in the simultaneous process of Gycolysis and Kreb’s cycle. Glycolysis is the breakdown of glucose to two pyruvic acids. These two pyruvic acids will be used for the production of carbon dioxide and water in Kreb’s cycle.

Posted in Chemistry

What are the 5 forms of energy

mechanical energy, thermal energy, nuclear energy, chemical energy, electromagnetic energy 

Posted in Chemistry

Which reason best explains why metals are shiny? because their valence electrons reflect light/ because their valence electrons absorb light/ because their valence electrons oscillate between bands/ because their valence electrons move to higher energy levels

Answer: Option (c) is the correct answer.

Explanation:

It is known that metals have free electrons. These free electrons when come in contact with light, vibrate or oscillate at their respective position. As a result, the electrons gain small amount of energy and when this energy is released the surface of metal  shines.

Thus, we can conclude that metals are shiny because their valence electrons oscillate between bands.

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What is the energy of an electromagnetic wave with a frequency of 8•10^12 Hz?

Hello!

Find the Energy of the Photon by Planck's Equation, given:

E (photon energy) =? (in Joule)

h (Planck's constant) =  6.626*10^{-34}\:J * s

f (radiation frequency) =  8*10^{12}\:Hz

Therefore, we have:

 E = h*f

 E = 6.626*10^{-34}*8*10^{12}

 E = 53.008*10^{-34+12}

 E = 53.008*10^{-22}

 \boxed{\boxed{E = 5.3008*10^{-21}\:Joule}}\end{array}}\qquad\checkmark

I Hope this helps, greetings ... DexteR! =)

Posted in Chemistry

What happens to energy when Sally kicks a soccer ball? A. Kinetic energy is transformed to chemical energy in muscles. B. Potential energy is transformed to chemical energy in muscles. C. Kinetic energy is transferred from the leg to the soccer ball. D. Potential energy is transferred from the leg to the soccer ball.

Answer : Option C) Kinetic energy is transferred from the leg to the soccer ball.

Explanation : As sally kicks the soccer ball the kinetic energy that is generated from his leg gets transferred into the soccer ball which is set into motion in a particular direction where it was aimed. From the position of rest the soccer ball was set into motion by the kick of sally's leg was because of the energy transformation process from sally's leg into the soccer ball.

Posted in Chemistry

Kumar is producing the photoelectric effect by using red light. He wants to increase the energy of emitted electrons. Based on the research of Albert Einstein, what is the best way for him to do this?

Explanation:

Photoelectric effect: Electrons are ejected out from the surface of metal when light of sufficient frequency falls upon shiny surface of metals. light is made up small bundles of energy packets named photons which when falls on surface transfer their energy to electrons due which electrons ejects out of the metallic surface. The energy for one photon was given by expression:

E=h\nu, or E\propto \nu

h=Planck's constant, \nu= frequency of the light

Kumar can increase the energy of emitted electron by using light with higher value of frequency than the frequency of red light. This is because the energy  carried by the photon of a light is directly proportional to the frequency of the light. Higher the value of frequency of light higher will be the value of energy of a photon. And photon with higher energy will impart more amount of energy to an electron while ejection.

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How does Dr.Hoffmann's ultrasound device benefit society? ( modern chemistry textbook page 180).

Answer:

In 1966, Dr. Hoffmann recorded for the first time in medicine embryonic movements and the heartbeat of the fetus using an ultrasound system.

Explanation:

Today, ultrasound is a technique widely used by many medical specialties, in the emergency department, in intensive care or in daily practice.

In 1794, the Italian Spallanzani observed that during the flight of bats they did not collide with anything despite being blind. It is then that he theorizes that they emitted sounds imperceptible to the man he would call ultrasounds, which they capture with their ears after bouncing off objects.

In 1842, Christian Doppler's first article on the effect of his name appears.

In 1912, Richardson suggests the use of ultrasonic echoes to detect submerged objects, creating the first ultrasonic generator five years later by Paul Langevin and Chilowsky.

Since then the applications of this new technology have been unstoppable, especially in medicine.

Posted in Chemistry

New cells are created from A) matter. B) energy. C) other cells. D) non-living matter.

Answer: C)  other cells.

Explanation: I took the Pre-Test on USA Test Prep.

Posted in Chemistry

How much heat energy is need to raise the temperature of 500.0 g of Aluminum from 15.0°C to 20.0°C? The specific heat of aluminum is 0.899 J/g°C. *

The amount of heat energy that is needed to raise the temperature of a system can be calculated by the product of the mass, heat capacity of a substance and the temperature difference. We calculate as follows:

Q = mC(T2-T1)
Q = 500 (0.899) (20 - 15)
Q = 2247.5 J

Posted in Chemistry

What happens if the amount of energy that is absorbed by the reactants is less than the activation energy? The reaction does not occur. The reaction occurs very quickly. The reaction occurs very slowly. The reaction occurs spontaneously.

Answer: Option (a) is the correct answer.

Explanation:

Activation energy is the minimum amount of energy required by the reactant molecules to complete a reaction.

Thus, the energy absorbed by the reactant molecules helps in breaking of their chemical bonds as a result reaction takes place.

If the amount of energy that is absorbed by the reactants is less than the activation energy then the chemical bond between reactant molecules will not break as a result the reactant molecules will not participate in the reaction.

Thus, we can conclude that the reaction does not occur if the amount of energy that is absorbed by the reactants is less than the activation energy.

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