Answer:
Explanation:
Efficiency of the electric power plant is 
Here Temperature of hot source 
and Temperature of sink 
Hence the efficiency is
Now another formula for thermal efficiency Is

Here QI is the of heat taken from source 100 MJ ; Q2 of heat transferred to the sink (river) to be found
W is the of work done and W = QI -Q2
Hence From

Hence the of heat transferred to the river Is 
Answer: -22.2 kJ
Explanation:
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
SGDSDGSDGSDGgsg
According to Hess’s law, the chemical equation can be treated as algebraic expressions and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
(1)

(2)

(3)

Reversing 1 ,2 and 3 and halving 1 and 2 and then adding we get net equation:
(4)


Therefore, the heat of reaction, ΔH, for the reaction is -22.2 kJ
I will state the electronegativities of each element.
Ca = 1.00
F = 3.98
H = 2.20
P = 2.19
Na = 0.93
The highest electronegative element is F (Fluorine).
Answer:
construct using only recycled materials ^^
Explanation: