Question

Hydrogen bromide breaks down into diatomic hydrogen and bromine in the reaction shown. 2HBr - H2 + Br2
The energy of the reactant is 732 kJ/mol and the energy of the products is 630 kJ/mol. What is the total energy of the reaction? Is this reaction endothermic or exothermic?
(1 point)
A. -102 kJ/mol, endothermic
B. 102 kJ/mol, exothermic
C. 102 kJ/mol, endothermic
D. -102 kJ/mol, exothermic​

Answer 1

The total energy of the decomposition reaction of hydrogen bromide to form diatomic hydrogen and bromine, with an energy of the reactants and products equal to 732 kJ/mol and 630 kJ/mol, respectively, is 102 kJ/mol. The correct option is C.

The decomposition reaction is:

2HBr → H₂ +Br₂

The total energy is given by:

$\Delta H = \Delta H_{r} - \Delta H_{p}$

Where:

$\Delta H_{r}$: is the change of energy of the reactants = 732 kJ/mol

$\Delta H_{p}$: is the change of energy of the products = 630 kJ/mol

Hence, the total energy of the reaction is:

$\Delta H = \Delta H_{r} - \Delta H_{p} = (732 - 630) kJ/mol = 102 kJ/mol$

The positive result means that this reaction is endothermic, thus this reaction needs 102 kJ/mol to break the hydrogen bromide bond to form diatomic hydrogen and bromine.  

Therefore, the correct option is C.

You can learn more about the endothermic and exothermic reactions here: https://brainly.com/question/11753370?referrer=searchResults

I hope it helps you!    

Answer 2

Answer:

102 kJ/mol, endothermic

Explanation:

1- B

2- D

3- B

4- C

5- D

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