You can use this formula to help:
Where:
C = specific heat
q = heat
m = mass
t = temperature
What we know:
C = unknown
q = 956 J
m = 45 g
change in t = 12°C because 37°C - 25°C = 12°C
Plug known values into the formula:
C = 956 J / (45 g) (12°C) and we are left with a specific heat of 1.77J/g°C
Now, convert Joules to calories and then you get:
Answer: A. 0.423 cal/g°C
<u>Answer:</u> The value of is -163 kJZ
<u>Explanation:</u>
The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:
......(1)
We are given:
Given mass of water = 72.0 g
Molar mass of water = 18 g/mol
Putting values in equation 1, we get:
Calculating the heat released for the condensation process:
......(2)
where,
= amount of heat released
n = number of moles of water = 4 moles
= specific heat of vaporization = -40.7 kJ/mol
Negative sign represents the amount of heat released.
Putting values in equation 2:
Hence, the value of is -163 kJ