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Grade 12th passPhysical Chemistry

The amoun of ice that will remain when 52 g of ice is added to 100g of water at 40oc is .....g at stage o: thermal equibirium at 0oc

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8 Years agoGrade 12th pass
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1 Answer

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ApprovedApproved Tutor Answer1 Year ago

To determine the amount of ice that remains when 52 g of ice is added to 100 g of water at 40°C, we need to consider the principles of thermal equilibrium and the specific heat capacities involved. The process involves heat transfer between the water and the ice until they reach a common temperature, which in this case is 0°C, the melting point of ice.

Understanding the Heat Transfer Process

When ice is added to warmer water, heat will flow from the water to the ice. This heat transfer will cause the ice to melt and the temperature of the water to decrease until thermal equilibrium is reached. We can break this down into a few logical steps:

Step 1: Calculate the Heat Required to Melt the Ice

The heat required to melt ice can be calculated using the formula:

  • Q = m × Lf

Where:

  • Q is the heat absorbed (in joules),
  • m is the mass of the ice (in grams), and
  • Lf is the latent heat of fusion for ice, which is approximately 334 J/g.

For 52 g of ice:

  • Q = 52 g × 334 J/g = 17368 J

Step 2: Calculate the Heat Lost by the Water

The heat lost by the water as it cools down can be calculated using the formula:

  • Q = m × c × ΔT

Where:

  • m is the mass of the water (in grams),
  • c is the specific heat capacity of water (approximately 4.18 J/g°C), and
  • ΔT is the change in temperature (in °C).

For 100 g of water cooling from 40°C to 0°C:

  • ΔT = 40°C - 0°C = 40°C
  • Q = 100 g × 4.18 J/g°C × 40°C = 16720 J

Step 3: Compare Heat Gained and Lost

Now we can compare the heat gained by the ice to the heat lost by the water:

  • Heat required to melt the ice: 17368 J
  • Heat lost by the water: 16720 J

Since the heat lost by the water (16720 J) is less than the heat required to melt all the ice (17368 J), not all of the ice will melt. We need to find out how much ice can melt with the available heat from the water.

Step 4: Calculate the Amount of Ice That Melts

To find the mass of ice that can melt with the available heat, we can rearrange the melting formula:

  • m = Q / Lf

Using the heat lost by the water (16720 J):

  • m = 16720 J / 334 J/g ≈ 50.0 g

Final Calculation: Amount of Ice Remaining

Since we started with 52 g of ice and approximately 50 g can melt, the amount of ice that remains is:

  • Remaining ice = Initial ice - Melted ice
  • Remaining ice = 52 g - 50 g = 2 g

Thus, when 52 g of ice is added to 100 g of water at 40°C, approximately 2 g of ice will remain when thermal equilibrium is reached at 0°C.