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## How is an exothermic reaction identified on a potential energy diagram?

### Answered by answersmine AT 22/10/2019 – 02:30 AM

Energy diagrams are use to depict the energy changes that occur during a chemical reaction. There are two types of reaction based on the energy change, these are exothermic and endothermic reactions. In endothermic reactions energy are gained while in exothermic reactions energy are lost to the environment. To identify an exothermic reaction on a potential energy diagram, one has to compare the potential energy of the reactants and the products. If the potential energy of the product is less than that of the reactants, the reaction is exothermic.

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## What is the potential difference between the plates after a sheet of teflon is inserted between them?

Capacitance C of a parallel plate capacitor is C=Q/V, where Q is the charge on the plates and V is the potential difference between the plates. The potential of the capacitor is then: V=Q/C.

The capacitance C is given by the equation C=k*ε₀*(A/d) where k is the dielectric constant, ε₀ is the permittivity of free space, A is the surface of the plate and d is the distance between the plates.

For vacuum and air, k=1 so the capacitance is C=ε₀*(A/d).

But when we insert a dielectric between the plates like teflon which has k=2.1 at T=20°C the capacitance becomes:

C₁=k*ε₀*(A/d)=2.1*ε₀*(A/d)=2.1*C.

We can see that the capacitance increases by k=2.1 which is the dielectric constant of teflon.

So the voltage V becomes:

V₁=Q/C₁=Q/(2.1*C)=(1/2.1)*(Q/C)=(1/2.1)*V=0.48*V.

V₁=0.48*V.

Potential difference decreases by 0.48 because we inserted teflon between the plates.

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## What is a potential benefit of fuel cell cars? increased efficiency converting gasoline to energy no recharging necessary decreased automobile cost larger engines

What is a potential benefit of fuel cell cars? increased efficiency converting gasoline to energy no recharging necessary decreased automobile cost larger engines

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## How is energy converted in a hydroelectric plant? A) The kinetic energy of water is converted to electrical energy when water flows down the dam's channel and into the transformer. B) The potential energy of water is converted to electrical energy when water flows past a generator. C) The kinetic energy of water turns turbines; the mechanical energy of the turbines turns the generator, which produces electrical energy. D) The potential energy of water turns the generator's turbines, which results in the production of electrical energy.

How is energy converted in a hydroelectric plant? A) The kinetic energy of water is converted to electrical energy when water flows down the dam’s channel and into the transformer. B) The potential energy of water is converted to electrical energy when water flows past a generator. C) The kinetic energy of water turns turbines; the mechanical energy of the turbines turns the generator, which produces electrical energy. D) The potential energy of water turns the generator’s turbines, which results in the production of electrical energy.

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## Which is the first surface that has the potential to come into contact with solar radiation? -icebergs clouds the ocean land

The Sun is located
at the center of our Solar System, at a distance of about 150 x 106 kilometers from
Earth. The Sun produces  solar heat energy. This energy travels through space in the form of electromagnetic
waves. The process of heat transfer is known as radiation.Before reaching the sea-level the sun’s rays have to pass through the whole thickness of the atmosphere.
So, the first surface that has the potential to come into contact with solar radiation are the clouds.

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## Which energy changes are associated with a liquid freezing? Energy is released as potential energy increases. Energy is absorbed as potential energy increases. Energy is released as potential energy decreases. Energy is absorbed as potential energy decreases.

Which energy changes are associated with a liquid freezing? Energy is released as potential energy increases. Energy is absorbed as potential energy increases. Energy is released as potential energy decreases. Energy is absorbed as potential energy decreases.

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## It is evident that the nation is experiencing a recessionary gap when potential output is less than aggregate output. potential output is decreasing at a rate greater than aggregate output is increasing potential output is decreasing. aggregate output is less than potential output. aggregate output is greater than potential output.

### Answered by answersmine AT 22/10/2019 – 04:27 AM

A recessionary gap is condition wherein the economy is operating below the full capacity of its employment level. An indication that an economy is experiencing a recessionary gap is when
aggregate output is less than potential output
The answer is the 4th option.

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## A 66-year-old client is already being treated for hypertension. his doctor, concerned about the potential for heart failure, has him come back for check-ups regularly. what does hypertension have to do with heart failure?

The answer to this question is that Hypertension
caused the heart chambers to enlarge and weaken. Hypertension is also known in having
a high blood pressure. Hypertension if not treated can lead to a possible
stroke and heart attack. Those who are obese and overweight and with existing
health conditions like chronic kidney disease, high cholesterol, and
cardiovascular disease can make a person at risks for hypertension.

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## The typical state of a neuron is the _____, but when electrical signals stimulate it to its threshold, the _____ is immediately observed. resting potential; action potential action potential; refractory period action potential; resting potential resting potential; refractory period

The typical state of a neuron is the _____, but when electrical signals stimulate it to its threshold, the _____ is immediately observed. resting potential; action potential action potential; refractory period action potential; resting potential resting potential; refractory period

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## The sequence of processes that links the action potential to contraction is called

There are two systems in the human body that are responsible for the coordination between the functions of different systems to achieve the unity of the living organism’s body. These two systems are the nervous system and the endocrine system. The action of the nervous system is fast and takes a short time, while the action of the endocrine system is slow and takes a long time.

The functional unit of the nervous system is the nerve cell or the neuron. The neuron consists of a cell body and the axon. The cell body starts with the dendrites that receive the messages or the impulses from other neurons or from different sense organs or receptors. These impulses are then transmitted through the cell body. The cell body contains a nucleus and different organelles which help the nerve cell to perform its functions. The nerve impulse is then transmitted to the axon.

The axon is an extension from the cell body. There are some cells called Schwan cells that secrete a myelin sheath to insulate the axon from the surrounding medium. The insulated axons have more ability to conduct the impulses than non-insulated axons. The axon ends with the terminal arborizations. The terminal arborizations of a nerve cell connect to the dendrites of the next cell or to the afferent organ. The gaps between the dendrites and the terminal arborizations are called the synapses.

The nerve impulse is an electrochemical phenomenon i.e. an electrical phenomenon with a chemical nature. The membrane of the axon acts as a barrier between an outside positively charged medium and an inside negatively charged medium. This makes a potential difference of  -70mV. This state is called the resting potential. When the membrane is subjected to a stimulus, the positive charges enter to inside and the negative charges exit to the outside. The potential difference now becomes +40mV. This state is called the depolarization state. The point of stimulation acts as a new stimulus for the next point and so on. The membrane sooner gains its permeability again and the positive charges return to the outside and the negative charges to inside. This state is called repolarization.

The nerve impulse reaches the synapse. There are some neurotransmitters that are excited by the nerve impulse coming and carry the message across the membrane. Some receptors receive theses neurotransmitters on the dendrites of the next neuron. These receptors act as a stimulus for the new cell.

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## An electrochemical cell has the following overall reaction. Mn(s) + Cu2+(aq) mc018-1.jpg Cu(s) + Mn2+(aq) The reduction half-reaction has a standard potential of 1.18 V. The oxidation half-reaction has a standard potential of 0.34 V. What is the overall cell potential? 1. –1.52 V 2. –1.18 V 3 .+1.18 V 4. +1.52 V

An electrochemical cell has the following overall reaction. Mn(s) + Cu2+(aq) mc018-1.jpg Cu(s) + Mn2+(aq) The reduction half-reaction has a standard potential of 1.18 V. The oxidation half-reaction has a standard potential of 0.34 V. What is the overall cell potential? 1. –1.52 V 2. –1.18 V 3 .+1.18 V 4. +1.52 V

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## Arrange the balls in order from greatest amount of gravitational potential energy to least

Arrange the balls in order from greatest amount of gravitational potential energy to least

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## In which situations is gravitational potential energy present? Check all that apply. A person walks up a flight of stairs. A person runs across a room. Wind blows against a steel table anchored to the ground. Wind lifts a balloon into the air. A weightlifter holds a barbell on the ground. A weightlifter holds a barbell straight overhead

1) Water has very high specific heat.

2) It expands when it freezes

3) ability to dissolve in ionic substances

4) Water molecules at the surface experience fewer hydrogen bonds than water molecules within the liquid.

Explanation:

1) Water molecules due to their high specific heat , undergo relatively less increase in temperature after absorbing heat. So they prevent their adjoining area to experience sharp increase in temperature.

2) Water is an example which expands on freezing. In it , large spaces are left between molecules when it cools. It happens because hydrogen bonds prevent any two molecules to come very close thereby  creating gaps. This gap is filled up when ice melts , which results in overall reduction in volume of water.

3) Uneven distribution of charge results in water molecules becoming polar in nature . A polar substance  can be dissolved in polar solvents only.

4) It is due to property of surface tension. Property  of surface tension results due to molecules of water near the surface experiencing a  net downward  force due to hydrogen bonds . It is due to fewer hydrogen bonds made by them.

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## What has the greatest potential to demotivate you and lead you to unproductive activities? goals that are difficult to achieve multiple goals within a short-term period goals that are the same as other people’s goals restructuring a long-term goal

What has the greatest potential to demotivate you and lead you to unproductive activities? goals that are difficult to achieve multiple goals within a short-term period goals that are the same as other people’s goals restructuring a long-term goal

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## Which statement defines reduction potential when considering a pair of half-cell reactions? The half-reaction with the greater SRP has a greater tendency to gain electrons. The half-reaction with the lower SRP has a greater tendency to gain electrons. If each half-reaction has an SRP greater than zero, there will be two reduction reactions. If each half-reaction has an SRP less than zero, there will be two oxidation reactions.

The coefficient of CO₂ is 5.

Explanation:

Balancing the reaction:

___C₅H₁₂ + ___O₂ → ___CO₂ + ___H₂O

There are 5 C in the left side, so we put 5 on the right side:

___C₅H₁₂ + ___O₂ →  5CO₂ + ___H₂O

There are 12 H in the left side, so we put 6 as the coefficient of H₂O:

___C₅H₁₂ + ___O₂ →  5CO₂ + 6H₂O

Finally, there are 16 O in the right side, so we put 8 as the coefficient of O₂

___C₅H₁₂ + 8O₂ →  5CO₂ + 6H₂O

The coefficient of CO₂ is 5.

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## Biodiversity enhances ________ because it provides genetic diversity and the potential for developing more productive food crops that are disease resistant and adaptive to drought.

In tropical rain forest, the animals will have to deal with higher temperatures and greater rainfall. One example of an adaptation they might need is a thin, water-proof coat. This will prevent heat from becoming trapped inside their fur/hair/feathers, and the water-absorbing coating will allow water to stick to the inside of the coat without being absorbed, where the water will absorb the heat instead of themselves, and will cool the through evaporative cooling (heat release through evaporation)

In a deciduous forest, there is much colder temperatures, and significantly less rainfall. These animals would likely want a thicker water-proof coat. This is because the thicker coat would allow heat to become trapped, keeping them warm in the winter, and the water-proof coating prevents water from freezing in their fur, making them colder.

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## A vacancy has arisen in the district court in the state where a democratic senator holds office. in the process of identifying potential nominees for lower-court judgeships in the state, the deputy attorney general seeks the senators recommendations. in this scenario, this action of the deputy general can be referred to as

In literature, “mood” refers to the general feeling that a piece creates within the reader through the use of words and descriptions.

In this excerpt, the author gives several descriptions that make the situation sound difficult, unpredictable and exciting, such as: “deafening noise,” “made the alarm… more intense,” and “a state of anxiety.” These words evoke an exhilarating feeling in the reader.

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## When an electron moves 2.5 m in the direction of an electric field, the change in electrical potential energy of the electron is 8×10-17j. what is the strength of the electric field that causes the change in potential energy?

The gravitational force Fg between two objects is given by the equation:

Fg=(G*m₁*m₂)/r₂, where G=6.67*10^-11 m³ kg⁻¹ s⁻² is the gravitational constant, m₁ and m₂ are the masses of the two bodies and r is the distance between those bodies.

Due to the gravitational attraction the pencil and the eraser will attract if we there is no friction on the surface.

m₁=10 g=0.01 kg is the mass of the pencil
m₂=20 g=0.02 kg is the mass of the eraser
r=2.5 cm = 0.025 m

First we calculate the Fg:

Fg={(6.67*10^-11)*0.01*0.02}/(0.025²)=2.1344*10^-11 N

To get the velocity v of the pencil:

v²=2as, where a is the acceleration of the pencil and s is the path. In our case s=r so we can write:

v²=2ar

a=Fg/m₁= 2.133*10^-9 m/s²

v²=2*(2.133*10^-9)*0.025=1.0665*10^-10

v=√(1.0665*10^-10)=1.0327*10^-5 m/s

We have the velocity and the acceleration, so we can calculate the time t with the equation:

t=v/a=(1.0327*10^-5)/(2.133*10^-9)=4841.6 s

1 hour has 3600 s so when we divide time t in seconds by 3600 we get time T in hours:

T=t/3600=4841.6/3600=1.3449 h.

So the time for the pencil and eraser to touch is T=1.3449 hours.

Also time T can be expressed like T= 1h and 20 mins and 41.64 s

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## According to the collision theory and model created to explain the collision theory, what two factors must be satisfied for a given collision to be successful and result in the production of products? correct molecular shape and momentum. correct position and maximum potential. correct density and threshold velocity. correct orientation and sufficient energy.

According to the collision theory and model created to explain the collision theory, what two factors must be satisfied for a given collision to be successful and result in the production of products? correct molecular shape and momentum. correct position and maximum potential. correct density and threshold velocity. correct orientation and sufficient energy.

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## Consider what you know about pedigrees. How could doctors use pedigrees to prevent and treat disease? How could knowing about your genetic history and potential for disease affect your family, social, and work life?

Consider what you know about pedigrees. How could doctors use pedigrees to prevent and treat disease? How could knowing about your genetic history and potential for disease affect your family, social, and work life?

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## A researcher compared the recidivism rates of drug abusers that were given probation with those that were sentenced to prison and discovered that the recidivism rates were highest for those sentenced to prison. what potential error is reflected by this conclusion

The correct answer is D. The North American Free Trade Agreement or NAFTA is  signed in 1994. by Canada, Mexico, and the United States, making a trilateral trade bloc in North America. It is going to replaced by the 2018 United States, Mexico, Canada Agreement. Since it is a trade agreement, it is supposed to increase trade between these countries which will result in the increased production. Donald Trump said that he was pulling out of NAFTA and that would have a range of consequences for the U.S.  including reduced access to the export markets, reduced economic growth, and increased prices for gasoline, cars, fruits, and vegetables.

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## Glucose contains ________. a. osmotic energy b. kinetic energy c. potential energy d. both osmotic and kinetic energy

Explanation:

adenosine triphosphate(ATP) molecule acts as the energy currency for the cell because the energy needed for the various types of functions in the body and for the metabolism process is provided in the form, of adenosine triphosphate.

adenosine triphosphate is an organic molecule that stores energy which is used by the body to perform various activities.

adenosine triphosphate(ATP) is produced by  a process called oxidative phosphorylation with help of an enzyme ATP synthase

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## The nurse caring for a client with a large leg wound notes that the client’s past medical history includes diabetes, chronic atrial fibrillation, asthma controlled by maintaninence medication, and neuropathy. which one has the greatest potential to negatively impact the healing of the client’s wound?

Preferences are an example of an internal influence on thoughts or feelings.  Correct answer: A

Internal influence on thoughts or feelings are linked to the personality, and not the external environment. Personality is defined as the thoughts, emotions, intentions and behavior that people express as they move through their environment. It influences how we select, organize, and interpret information.

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## What is the potential severity of the illnesses you are most susceptible to

1. This type of immunity would be passive artificial immunity. Passive artificial immunity is the injection of serum that makes human body invulnerable to specific diseases. But the effect of this serum is temporary. To refresh its effect you should to make the injection again. Sure, you can do it only in advice of your doctor.

2.

According to the information given above, I think that the nurse is aware that the most serious toxic effect of acute acetaminophen overdose is hepatic necrosis. Hepatic necrosis is a serious liver failure that can be caused by toxic injuries of acute acetaminophen (or others medicines) overdose.

3. In my opinion, nurse should respond like this: “

It is normal for children this age to regress during a stressful event like a hospitalization. Try to calm down your child and say her that everything is going to be okay.”

4. The most appropriate response by the nurse is:

“Tattoos are invasive and there is the potential for disease with their application.” Girl should find tattoo parlor with appropriate conditions to make tattoo without a risk getting infected.

5. Referring to Women’s Health Initiative study, hormone replacement therapy has a potential risk of breast cancer

and myocardial infarction and stroke may outweigh the potential benefit of alleviating symptoms associated with menopause.

6. I am completely sure that the most likely cause is

fibrocystic disease, which results from hormonal changes during the menstrual cycle. Sure it’s necessary to undergo medical examination to prevent the possible breast cancer.

7. I think that the cause of her vaginitis is antibiotics. Long antibiotic therapy eliminate bacilli that create healthy vaginal environment. This can lead to growth of microorganisms which can lead to vaginitis.

8. According to the information given above, the nurse should say that girl needs to avoid prolonged sun exposure to prevent a common side effect of this medication. Prolonged sun exposure can cause scorches.

9. The nurse should recommend him to recheck his blood pressure within two months. Hypertension is more prevalent in black communities and blood pressure 150/90 mm Hg is not normal. So it would be necessary to check his pressure at least every 2 months.

10. As far as I remember “

A spinal cord injury patient has no awareness of the need to void” is considered as a reflex (neurogenic) incontinence. Reflex incontinence is caused by a dysfunction in the detrusor muscle.

11. I am definitely sure that the nurse should encourage the patient to see her gynecologist as soon as possible. In

perimenopausal period all women should make annual checkups that include vaginal examination.

12. In my view, when planning this patient’s care, the nurse should prioritize the r

isk for infection related to suppressed bone marrow function. There is a risk of leukopenia and subsequent infection because doxorubicin suppresses bone marrow function.

13. I think that the most appropriate explanation of the disease sounds like this: “

Tissue similar to the lining of the uterus has implanted in areas outside the uterus.” A benign lesion grows aberrantly anywhere in the pelvic cavity outside the uterus.

14. I am pretty sure that w

hen the needle is inserted and the mass is no longer palpable, this mass may become cystic and was ruptured when the needle was inserted.

15.

The nurse recognizes in this situation the boy’s attempt to master the primary developmental step of school age, which is called industry. Industry is a sense of learning how to master your skills. In this situation, boy wants to show the nurse his skills and then to master them because he wants to become a doctor.

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