511.2 grams of chlorine gas consumed (with excess H-) when
1,342.0 kJ of energy is released from the system.
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What is an exothermic reaction?</h3>
In thermochemistry, an exothermic reaction is a "reaction for which the overall standard enthalpy change ΔH⚬ is negative."
Given that 1 mole of chlorine releases -184.6 energy.
Then, we have to find the number of moles of chlorine when 1,342.0 kJ of energy is released from the system.
So, calculating number of moles of chlorine.
Moles = 
Moles = 7.2 mole
Now, calculating number mass of chlorine.

Mass = 7.2 mole x 71 g/mole
Mass = 511.2 gram
Learn more about exothermic reaction here:
brainly.com/question/10373907
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To calculate the amount of heat transferred when an amount of reactant is decomposed, we must look at the balanced reaction and its corresponding heat of reaction. In this case, we can see that 252.8 kJ of heat is transferred per 2 moles of CH3OH used. When 22 g of CH3OH is used, 86.9 kJ is absorbed.
Answer:
I think the answer is the 3rd one
Really? Really!?
IT'S SCIENCE!