Answer : The value of for the reaction is +571.6 kJ/mole.
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.
According to this law, the chemical equation can be treated as ordinary algebraic expression 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.
The given chemical reaction is,
Now we have to determine the value of for the following reaction i.e,
According to the Hess’s law, if we reverse the reaction then the sign of change.
So, the value for the reaction will be:
Hence, the value of for the reaction is +571.6 kJ/mole.
<u>Answer:</u>
<em>When we finish, the temperature would be 32.5℃</em>
<em></em>
<u>Explanation:</u>
Density of water = mass/volume
So,
Mass of water = Density × Volume
where
= Final T - Initial T
Q is the heat energy in calories
c is the specific heat capacity (for water 1.0 cal/(g℃))
m is the mass of water
plugging in the values
Final T = ∆T + Initial T
= 7.5℃ + 25℃ = 32.5℃ (Answer).