Question

1. How much energy must be removed from a 200 g block of ice to cool it from 0 degrees C to -20 degrees C? The specific heat of ice is 2090 (J / kg⋅k)

Express your answer to two significant figures and include the appropriate units.

Answer 1

The amount of energy that must be removed from a 200 g block of ice to cool it from 0 degrees C to -20 degrees C can be calculated using the formula:

Q = m * c * ΔT

where Q is the amount of energy, m is the mass, c is the specific heat, and ΔT is the change in temperature.

First, we need to convert the mass of the ice from grams to kilograms:

m = 200 g = 0.2 kg

Next, we need to calculate the change in temperature:

ΔT = (-20°C) - (0°C) = -20°C

Now we can plug in the values and solve for Q:

Q = (0.2 kg) * (2090 J/kg⋅K) * (-20°C) = -8360 J

The amount of energy that must be removed from the ice is 8360 J. Answer: -8360 J.