How much heat is needed to increase the temperature of 60 g of H2O from ice at -5C to liquid at 20C?
q1 = heat to move T of ice at 5C to ice at zero C.
q1 = mass ice x specific heat ice3 x (Tfinal-Tinitial)
q2 = heat to melt the ice at zero C to liquid water at zero C.
q2 = mass ice x heat fusion
q3 = heat to move liquid water from zero C to 20 C.
q3 = mass H2O x specific heat H2O x (Tfinal-Tinitial)
Qtotal = q1 + q2 + q3.
To determine the amount of heat needed to increase the temperature of a substance, we can use the formula:
Q = m * c * ΔT
Where:
Q is the heat (in joules or calories),
m is the mass of the substance (in grams),
c is the specific heat capacity of the substance (in joules per gram per degree Celsius, or calories per gram per degree Celsius), and
ΔT is the change in temperature (in degree Celsius).
In this case, we need to calculate the heat required to increase the temperature of 60 grams of H2O from -5°C (ice) to 20°C (liquid). Let's break down the calculation into two steps:
1. First, let's calculate the heat required to warm up the ice to its melting point (0°C).
ΔT1 = 0°C - (-5°C) = 5°C
2. Next, let's calculate the heat required to melt the ice at its melting point (0°C) to reach the desired temperature of 20°C.
ΔT2 = 20°C - 0°C = 20°C
Now, we need to look up the specific heat capacity of ice and liquid water.
Specific heat capacity of ice (c1): 2.09 J/g°C
Specific heat capacity of liquid water (c2): 4.18 J/g°C
1. Heat required to warm up the ice:
Q1 = m * c1 * ΔT1
= 60 g * 2.09 J/g°C * 5°C
2. Heat required to melt the ice:
Q2 = m * c2 * ΔT2
= 60 g * 4.18 J/g°C * 20°C
Finally, we can add the two heat values calculated in steps 1 and 2 to find the total heat needed:
Q = Q1 + Q2
Using these formulas and specific heat capacities, you can calculate the total amount of heat required.