an unknown substance with mass of 1.2kg loses 32 kJ of thermal energy. which causes the temperature to drop from 364.0 k to 304.6 k. identify the unknown sustenance
To identify the unknown substance, we can use the equation for specific heat capacity:
Q = mcΔT,
where Q is the thermal energy transferred, m is the mass of the substance, c is the specific heat capacity of the substance, and ΔT is the change in temperature.
In this case, we are given Q as 32 kJ (which is equivalent to 32,000 J), m as 1.2 kg, and the initial and final temperatures as 364.0 K and 304.6 K, respectively.
Let's rearrange the equation to solve for the specific heat capacity (c):
c = Q / (m * ΔT).
c = 32,000 J / (1.2 kg * (304.6 K - 364.0 K))
c = 32,000 J / (1.2 kg * (-59.4 K))
c ≈ -449.83 J/(kg*K).
The specific heat capacity obtained (-449.83 J/(kg*K)) is negative, which is not physically possible. Therefore, there might be an error in the provided information or calculation. Please recheck the given data or calculations to get a valid value for the specific heat capacity.
To identify the unknown substance, we can use the formula:
q = m * ΔT * C
where:
q is the thermal energy transferred (in joules),
m is the mass of the substance (in kilograms),
ΔT is the change in temperature (in kelvin), and
C is the specific heat capacity of the substance (in joules per kilogram per kelvin).
We are given the following information:
m = 1.2 kg
ΔT = (364.0 K - 304.6 K) = 59.4 K
q = -32 kJ = -32,000 J (since the substance is losing thermal energy, the value of q is negative)
Now, rearranging the formula, we can solve for the specific heat capacity (C):
C = q / (m * ΔT)
C = -32,000 J / (1.2 kg * 59.4 K)
Calculating this:
C ≈ -449.83 J/(kg*K)
The negative value indicates an exothermic reaction or heat loss. However, specific heat capacity values are typically positive. It's possible that there was an error in the given information or calculation. Please verify the values provided and recalculate if necessary.