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0. A 5-kg block of ice is at a temperature of -27 °C. How much heat must be added to the ice to produce 5 kg of liquid water with a final temperature of 35 o C?

User JackLock
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2 Answers

2 votes

Final answer:

The amount of heat that must be added to the ice to produce 5 kg of liquid water with a final temperature of 35 °C is 2,683,950 J.

Step-by-step explanation:

To find the amount of heat required to produce 5 kg of liquid water from a 5 kg block of ice at -27 °C to a final temperature of 35 °C, we need to consider the different phases and temperature changes involved.

First, we need to find the heat required to raise the temperature of the ice from -27 °C to 0 °C. We can use the specific heat capacity of ice, which is 2.09 J/g°C. So, the heat required is:

Heat Q₁ = mass × specific heat capacity × temperature change

= 5000 g × 2.09 J/g°C × (0 °C - (-27 °C))

= 279,450 J

This heat will bring the ice to its melting point. To melt the ice, we need to use the latent heat of fusion, which is 334 J/g. So, the heat required to melt the ice is:

Heat Q₂ = mass × latent heat of fusion

= 5000 g × 334 J/g

= 1,670,000 J

After melting, the water needs to be heated from 0 °C to 35 °C. We can use the specific heat capacity of water, which is 4.18 J/g°C. So, the heat required is:

Heat Q₃ = mass × specific heat capacity × temperature change

= 5000 g × 4.18 J/g°C × (35 °C - 0 °C)

= 734,500 J

To find the total heat required, we can add up the individual heats:

Total heat = Q₁ + Q₂ + Q₃

= 279,450 J + 1,670,000 J + 734,500 J

= 2,683,950 J

Therefore, the amount of heat that must be added to the ice is 2,683,950 J.

User Rafael Steil
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4.1k points
3 votes

Answer:

Q = 2687130 J

Step-by-step explanation:

m = mass of block of ice = 5 kg


T_(i) = Initial temperature of ice block = - 27 °C


T_(f) = final temperature of water = 35 °C


c_(i) = specific heat of ice = 2108 J/(Kg °C)


L = Latent heat of fusion of ice = 334000 J/kg


c_(w) = specific heat of water = 4186 J/(Kg °C)

Heat added is given as


Q = m c_(i)(0 - T_(i))+ mL + m c_(w)(T_(f) - 0)


Q = (5) (2108)(0 - (-27))+ (5)(334000) + (5) (4186)(35 - 0)


Q = 2687130 J

User Xiaohua
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5.1k points