Mixing baking soda with vinegar to form CO2
(Isn't the one used to make volcano models)
Answer: Combustion changes the potential chemical energy into kinetic energy in the form of heat. For combustion an organic wood combines with oxygen already in the air and undergoes a chemical reaction that gives off carbon dioxide,water,and energy in the form of heat and light.
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:
pH=2.34
Explanation:
HBr -> H + Br
The dissociation it's complete, for that reason the concentration of the products is the same of HBr
[H+]=[Br-]=0.00234 M
pH= - log (0.00234)=2.34