Answer:
1.02 J/g°C.
Step-by-step explanation:
We can use the equation:
q = m * c * ΔT
where q is the heat absorbed or released, m is the mass of the substance (in grams), c is the specific heat, and ΔT is the change in temperature (in Celsius).
First, we can calculate the heat gained by the water:
q_water = m_water * c_water * ΔT_water
where m_water is the mass of the water (in grams), c_water is the specific heat of water (4.184 J/g°C), and ΔT_water is the change in temperature of the water.
m_water = 120 g
c_water = 4.184 J/g°C
ΔT_water = (32°C - 24°C) = 8°C
q_water = (120 g) * (4.184 J/g°C) * (8°C) = 4009 J
This means that the heat lost by the unknown solid is equal to the heat gained by the water:
q_solid = -q_water
q_solid = -4009 J
Next, we can calculate the change in temperature of the solid:
ΔT_solid = (32°C - 80°C) = -48°C
Now, we can solve for the specific heat of the solid:
q_solid = m_solid * c_solid * ΔT_solid
-4009 J = (90.0 g) * c_solid * (-48°C)
c_solid = -4009 J / (90.0 g * -48°C)
c_solid = 1.02 J/g°C
Therefore, the specific heat of the unknown solid is 1.02 J/g°C.