<span>If all chemical reactions that release free energy tend to occur spontaneously,why haven't all such reactions already occurred? One reason is that most reactions require an input of energy to get started.Before it is possible to form new chemical bonds,even bonds that contain less energy,it is first necessary to break the existing bonds,and that takes energy.The extra energy required to destabilize existing chemical bonds and initiate a chemical reaction is called activation energy.</span>
In the atom model, the poppy seeds are placed in different places to represent the different position of electrons.
Answer:-3463 kJ and -3452kJ
Explanation:
ΔU is the change in internal energy of a system and its formula is;
ΔU = q + w
Where q represents heat transferred into or out of the system. Its value is positive when heat is transfer into the system and negative when heat is produced by the system.
W represents the work done on or by the system. Its value is positive when work is done on the system and negative when it is done by the system.
For the system in this question, we see that it produces heat which means heat is transferred out of the system, therefore the value of q is negative, it can also be seen that work is done by the system which means that w is also negative.
Therefore,
ΔU = -q-w
ΔU = -3452 kJ – 11kJ
= - 3463kJ
ΔH is the change in the enthalpy of a system and its formuls is;
ΔH = ΔU + Δ(PV)
By product rule Δ(PV) becomes ΔPV + PΔV
At constant pressure ΔP = 0. Therefore,
ΔH = -q-w + PΔV
w is equals to PΔV, So:
ΔH = -q
ΔH = -3452kJ