How much heat energy, in kilojoules, is required to convert 76.0 g of ice at −18.0 ∘c to water at 25.0 ∘c ?

Answers

Answer 1
We should split the problem into three parts.

1) Amount of heat necessary to bring the ice from [tex]T=-18^{\circ} C[/tex] to [tex]T=0^{\circ} C[/tex]. This is given by:
[tex]Q=m C_{ice} \Delta T[/tex]
where [tex]m=76 g=0.076 kg[/tex] is the mass, [tex]\Delta T=18 ^{\circ} C=18 K[/tex] is the variation of temperature, and [tex]C_{ice} = 2.06 kJ/(Kg K)[/tex] is the specific heat of ice. Calculating, we get
[tex]Q=(0.076 kg)(2.06 kJ/(kg K))(18 K)=2.82 kJ[/tex]

2) When the ice is at [tex]T=0^{\circ} C[/tex], the heat added at this point does not change the temperature of the ice, because it is used to fuse it into water. The amount of heat needed to cause the complete fusion of ice is
[tex]Q=m L[/tex]
where [tex]L=334 kJ/kg[/tex] is the latent heat of fusion of ice. So,
[tex]Q=(0.076 kg)(334 kJ/kg)=25.38 kJ[/tex]

3) Now the ice is transformed into water. We have to bring it to [tex]T=25^{\circ} C[/tex], so the variation of temperature is [tex]\Delta T=25-0=25 ^{\circ} C=25 K[/tex]. The amount of heat needed to bring the water at this temperature is
[tex]Q=m C_{water} \Delta T[/tex]
where [tex]C_{water} = 4.186 kJ/(kg K)[/tex] is the specific heat of water. Therefore,
[tex]Q=(0.076 kg)(4.186 kJ/(kg K))(25 K)=7.95 kJ[/tex]

4) So, the total heat needed for the entire process is:
[tex]Q_{tot}=2.82 kJ + 25.38 kJ+7.95 kJ=36.15 kJ[/tex]


Answer 2
Final answer:

The total heat energy required to convert 76.0 g of ice at -18.0°C to water at 25.0°C is 35.184 kJ. This includes the energy to heat the ice to 0°C, melt the ice, and heat the water to 25°C.

Explanation:

To calculate the heat energy required, we need to account for three processes: heating the ice to 0°C, melting the ice, and then heating the water to 25°C.

For the first process, we use the formula Q=mcΔT, where m is mass, c is specific heat, and ΔT is the temperature change. Ice has a specific heat of 2.09 J/g°C. So Q = 76.0 g * 2.09 J/g°C * 18°C = 2854.56 J.

For the second part, we use the formula Q = mLf, where m is mass and Lf is heat of fusion. For ice, Lf = 334 kJ/kg or 334 J/g. So Q = 76.0 g * 334 J/g = 25384 J.

For the last process, we once again use Q=mcΔT, this time with the specific heat of water, 4.184 J/g°C. So Q = 76.0 g * 4.184 J/g°C * 25°C = 7946 J.

To get the total heat energy required, we add these three quantities together and convert from joules to kilojoules. Q_total = (2854.56 J + 25384 J + 7946 J) / 1000 = 35.184 kJ. So, it requires 35.184 kJ of heat energy to convert 76.0 g of ice at -18.0°C to water at 25.0°C.

Learn more about Heat Energy here:

https://brainly.com/question/25384702

#SPJ11


Related Questions

To get an spaceship into orbit, it has to move
about as fast as the speed of sound
about as fast as the speed of light
about 18,000 miles per hour
there is no minimum speed for orbital motion

Answers

The answer is the third option, "about 18,000 miles per hour". If you just want to get a spaceship into orbit around the Earth, the spaceship will need to reach a minimum speeds of about 4.9 miles per second, which is equivalent to 17,600 miles per hour (about 18,000 miles per hour to the nearest thousand).

A negatively charged object is located in a region of space where the electric field is uniform and points due north. the object may move a set distance d to the north, east, or south. rank the three possible movements by the change in electric potential energy (ue) of the object. rank from greatest increase to decrease in ue.

Answers

- The largest increase in potential energy occurs when the charge is moving north. This is because the charge is negative, so it acquires potential energy when moving in the same direction of the field (viceversa, a positive charge when moving in the direction of the field it loses potential energy converting it into kinetic energy). The amount of potential energy gained is equal to the product of the charge and the distance covered:
[tex]\Delta U = e d[/tex]

- The second largest increase is when the charge is moving east. In this case, actually, the variation of potential energy is zero. This is because the charge is moving perpendicular to the field, and so it is moving along points with same potential. Therefore, in this case the variation of potential energy is zero:
[tex]\Delta U = 0[/tex]

- Finally, when the charge is moving south, it loses potential energy. This is because it is moving against the electric field, and since it is a negative charge, in this direction it loses potential energy converting it into kinetic energy. Therefore, in this case:
[tex]\Delta U = - e d[/tex]

(a) There will be an increase in the potential energy when the charge moves North.

(b) The variation of potential energy will be zero when the charge is moving to the east.

(c)There is a loss in potential energy when a charge moves to the South.

What will be the potential energy of the charge at different directions?

(a) The largest increase in potential energy occurs when the charge is moving north. This is because the charge is negative,

so it acquires potential energy when moving in the same direction of the field (vice versa, a positive charge when moving in the direction of the field loses potential energy converting it into kinetic energy).

The amount of potential energy gained is equal to the product of the charge and the distance covered:

[tex]\rm \Delta PE=qD[/tex]

(b) The second-largest increase is when the charge is moving east. In this case, actually, the variation of potential energy is zero.

This is because the charge is moving perpendicular to the field, and so it is moving along points with the same potential. Therefore, in this case, the variation of potential energy is zero:

[tex]\rm \Delta PE=0[/tex]

(c) Finally, when the charge is moving south, it loses potential energy. This is because it is moving against the electric field,

since it is a negative charge, in this direction it loses potential energy converting it into kinetic energy. Therefore, in this case

[tex]\rm \Delta PE=-qD[/tex]

Thus

(a) There will be an increase in the potential energy when the charge moves North.

(b) The variation of potential energy will be zero when the charge is moving to the east.

(c)There is a loss in potential energy when a charge moves to the South.

To know more about Energy of the Charge follow

https://brainly.com/question/874116

Without inertia, how would an object that is experiencing a centripetal force behave?

It would move in a line away from the circle’s center.
It would move in a line toward the circle’s center.
It would move in a curved, circular path.
It would move in a line tangent to the circular path.

Answers

The correct option is this: IT WOULD MOVE IN A CURVED CIRCULAR PATH.
Objects that are travelling in circular paths change directions all the time as they move round the circle, but they are prevented from moving off in a straight line by centripetal force. The centripetal force keeps pulling the objects towards the center of the circle. 

B. It would move in a line toward the circle’s center.

Explanation:

got it right on edge 2022

Brad is working on a speed problem in physics class. The problem tells him that a girl runs from her house to the park 0.05 km away in 10 s. Brad calculates that her speed is 0.005 m/s. Is he correct? If not, explain the flaw or flaws in his problem solving process.

Answers

it is corecct becasue it 10 s more added from 0.05

Answer:

He is incorrect!  Her speed was 5m/s.

Explanation:

For calculating the speed, first we shall remember that:

[tex]v=\dfrac{d}{t}[/tex]

Where [tex]v[/tex] is the speed, [tex]d[/tex] is the distance travelled and, [tex]t[/tex] is the time it takes to travel distance [tex]d[/tex].

So one migth think that velocity can be easely compute:

[tex]v=\dfrac{0.05}{10}[/tex]

[tex]v=0.005\dfrac{m}{s}[/tex]

Be carefull, he does not make a proper dimensional analisis!  

Before computing the speed we must know in what dimensions our values are.

[tex]d=0.05km[/tex], distances is measure in Kilometers.

[tex]t=10s[/tex], time is measure in seconds.

If we want our speed to be in [tex]m/s[/tex], first we need to be sure that our values are expressed  in meters and seconds.

Time is already  expressed in seconds, distance is not in Kilometers.

So

[tex]0.05Km=50m[/tex],

now we can compute the speed:

[tex]v=\dfrac{d}{t}[/tex]

[tex]v=\dfrac{50m}{10s}[/tex]

[tex]v=\5dfrac{m}{s}[/tex]

You walk into an elevator, step onto a scale, and push the "up" button. you recall that your normal weight is 639 n . when the elevator has an upward acceleration of magnitude 2.90 m/s2 , what does the scale read?

Answers

This question deals with the concepts of the actual weight and apparent weight.

The apparent weight of the person is "827.9 N".

APPARENT WEIGHT

The apparent weight of an object is the reaction of the elevator floor on the person while the elevator is in accelerated motion. It is not the actual weight but the weight felt by the person for that time. In this case the elevator is moving up. Hence the apparent weight will be:

[tex]W_a=m(g+a)=mg+ma\\W_a=W+ma[/tex]

where,

W = actual weight = 639 Nm = mass = [tex]\frac{W}{g}=\frac{639\ N}{9.81\ m/s^2}[/tex] = 65.14 kga = acceleration = 2.9 m/s²[tex]W_a[/tex] = apparent weight = ?

Therefore,

[tex]W_a=639\ N + (65.14\ kg)(2.9\ m/s^s)[/tex]

[tex]W_a=827.9\ N[/tex]

Learn more about apparent weight here:

https://brainly.com/question/26393265

Final answer:

The scale reading in an elevator accelerating upwards will display an increased weight due to the additional force of acceleration. When an elevator accelerates with a magnitude of 2.90 m/s^2, the scale will show a higher value than the normal weight, calculated by the sum of gravitational force and force of acceleration.

Explanation:

When you step onto a scale in an elevator that is accelerating upwards with a magnitude of 2.90 m/s2, the scale reading will be higher than your normal weight due to the additional force required to accelerate you upwards. Given that your normal weight is 639 N, we can calculate the new scale reading by incorporating the effects of the elevator's acceleration using Newton's second law of motion.

To find the new scale reading, we first determine the apparent weight. The apparent weight is the sum of the true weight (gravitational force) and the force of acceleration (ma).

Apparent weight = True weight (W) + Force of acceleration (ma)

Where the true weight W = mg (mass times gravity), and a is the acceleration of the elevator.

Assuming Earth's gravity to be 9.81 m/s2, we can calculate the apparent weight as follows:

Apparent weight = mg + ma

Now, we need to find the mass (m) from the given weight (639 N), which is m = W/g = 639 N / 9.81 m/s2.

Then plug the mass and the given acceleration into the equation for apparent weight.

The scale reading in an accelerating elevator is directly proportional to the acceleration; it increases as the elevator accelerates upwards. However, once the elevator reaches a constant velocity, the scale reading will return to your normal weight, 639 N, because there will be no additional force from acceleration (a = 0).

How many cells must be connected in series to give the 350 v a large catfish can produce?

Answers

Each electrocyte can produce 110 mv.
110 m/V=0.110V
n(0.110)=350
n=3182 (rounded)

Final answer:

Approximately 2333 electro plaques, or biological cells, would be needed to be connected in series to produce 350 V, given that each cell produces 0.15 V.

Explanation:

To calculate the number of cells required to produce a voltage of 350 V, similar to what a large catfish can produce, we must understand that when cells are connected in series, the total voltage is the sum of the individual voltages of each cell. If each cell, similar to those in an electric eel, produces an electromotive force (emf) of 0.15 V, then the number of cells required to reach 350 V would be the total voltage desired divided by the voltage of one cell.

(350 V) / (0.15 V per cell) = 2333.33 cells

Therefore, approximately 2333 cells would need to be connected in series to produce 350 V. This figure is derived by understanding that the potential difference across each cell adds up when they are connected in a series circuit, a principle that is crucial in the functioning of biological cells called electro plaques in electric fish.

Other Questions
What is the biological definition of a species? A.a group of organisms that look alike B.a group of similar organisms that live in different areas C.a group of similar organisms that live in one particular area D.a group of organisms that can mate with each other and produce fertile offspring Our ability to recall an item from a list depends on where in the list the item occurs. this is the __________ effect. question 44 options: The railroad system was the impetus for the modern tourism industry.Please select the best answer from the choices providedTF Identify the type of communication illustrated in the quotation. "So Jason and Letecia, what do you guys want to do tonight after the game?" Intrapersonal Interpersonal Small group communication public communication When should you clean and sanitize surfaces and utensils Why is temperature less of a limiting factor in water biomes than in land biomes? A) Evaporation keeps water cool. B) Waves deflect the rays of the sun. C) Water reflects sunlight better than soil does. D) Large amounts of water stabilize temperatures. Why is it important to get enough sleep each night? A. Because sleep requirements may interfere with exercise schedules B. Because adequate sleep is as important to fitness as exercise and healthy eating C. Because sleep requirements may interfere with nutrition requirements D. Because adequate sleep guarantees a stress free day Study the underlined part of each sentence. In which sentence does the verb agree with the subject? a. The astronauts in the space capsule has a lot of training. b. Saturn, along with Jupiter and Uranus, have rings. c. The rings of Saturn contain mostly ice and rock. d. The purpose of the missions are to find out more about Mars. aluminum metal reacts with aqueous copper (II) chloride to forma aluminum chloride & copper metal. how many grams of copper are needed to react an entire 35 gram sample of aluminum The process that changes a solid directly into a gas is called sublimation. A solid that begins with a mass of 450 g will sublime to give off a gas with a mass of _______ g. Why are those who cannot be vaccinated for childhood diseases safer if everyone around them is vaccinated? Use the drop-down menus to label whether each sentence is a fused sentence, a comma splice, or a correct sentence. How and what techniques did Claude Monet use to compose the Haystacks paintings? Calculate the mass defect for oxygen-16 given this data. Round to the 5es001-1.jpg decimal place. mass of an oxygen-16 atom: 15.994914 amu mass of a proton: 1.00728 amu mass of a neutron: 1.00866 amu mass defect = amu which planet rotates different from the others how do jet streams influence local weather? Make a comparison between the governments roles in a capitalist economic system versus a socialist or communist economic system. A cube-shaped item needs to be painted. The items edge length is 2 centimeters. What is the total surface area that will be painted? 16 cm 24 cm 32 cm 48 cm Functionalist mile durkheim believed some deviance within society was What is the difference between two atoms of carbon having the same number of neutrons?a. nothingb. the number of protonsc. the number of electronsd. there may be differences in how they react with oxygen 2. (10 pt) what is the difference between an atom of silver and an atom of gold?a. one is new and the other is old.b. their net electrical charges are different.c. their atomic masses are different.d. more people would rather have one gold atom than a lot of gold?