Answer:
ΔHrxn = - 1534.3 J
Explanation:
Given the assumptions and the formula for the change in enthalpy:
ΔHrxn = m x C x ΔT, where
m is the mass of solution given 135.4 g
C is the heat capacity 4.2 J/g .K and,
ΔT is the change in temperature
we have ,
T₁ = ( 18.1 + 273) K = 291.1 K
T₂ = ( 15.4 +273) K = 288.4 K
ΔHrxn = 135.3 g x 4.2 J/gK x ( 288.4 -291.1 ) K = - 1534.3 J
After verifying our result has the correct unit, the answer is -1534.3 Joules, and the negative sign tells us it is an endothermic reaction decreasing the final temperature.
One way you can work out the rate of reaction is by the amount of product that is produced to time. This can also be done with heat and time.
Hope this helps! :)
To convert the given value to the desired one, use the proper unit conversions and dimensional analysis. Use the following conversion for the first set.
1 g = 100 cg
1 L = 1000 mL
Using the concept presented above,
V = (59800 cg/L)(1 g/100 cg)1 L/1000 mL)
V = 0.598 g/mL