From the statement of Hess' law, the enthalpy of the reaction A---> C is +90 kJ
<h3>What is Hess' law?</h3>
Hess' law of constant heat summation states that for a multistep reaction, the standard enthalpy of reaction is always constant and is independent of the pathway or intermediate routes taken.
From Hess' law, the enthalpy change for the reaction A ----> C is calculated as follows:
A---> C = A ---> B + B ---> C
ΔH of A---> C = 30 kJ + 60 kJ
ΔH = 90 kJ
Therefore, the enthalpy of the reaction A---> C is +90 kJ
The above reaction A---> C can be shown in the enthalpy diagram below:
A -------------------> C (ΔH = +90 kJ)
\ /
\ / (ΔH = +60 kJ)
(ΔH = +30 J) \ /
> B
Learn more about enthalpy and Hess law at: brainly.com/question/9328637
Answer:
millions of years sometimes even hundred of millions of years
To begin calculating, there is one thing you need to remember :

Then we have

As you know decomposition of 2moles now has prodused <span>196kj
So, </span><span>q is made due </span>


I'm sure it will help.
Hydrocarbons are carbon and hydrogen. Methane is CH4, and propane is C3H8. Methene is CH3, and propene is C3H6. Carbohydrates are hydrates of carbon. They <span>have the general formula (CH2O)x. thats how it differs
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Amino groups due to the chain can extend longer than the other