What is the specific heat of an unknown substance if a 2.53 g sample releases 13.1 cal as its temperature changes from 25.5°C to 21.3°C?
Hahah
To find the specific heat of an unknown substance, we can use the formula:
q = m * c * ΔT
Where:
q is the heat energy absorbed or released by the substance
m is the mass of the substance
c is the specific heat of the substance
ΔT is the change in temperature
In this case, we are given:
m = 2.53 g
q = -13.1 cal (negative sign indicates heat is released)
ΔT = 21.3 °C - 25.5 °C = -4.2 °C (negative sign indicates a decrease in temperature)
Plugging in the given values, we have:
-13.1 cal = (2.53 g) * c * (-4.2 °C)
Rearranging the equation to solve for c, we divide both sides of the equation by (2.53 g * -4.2 °C):
c = -13.1 cal / ((2.53 g) * (-4.2 °C))
Calculating the above expression, we get:
c ≈ 1.234 cal/(g°C)
Therefore, the specific heat of the unknown substance is approximately 1.234 cal/(g°C).