Answer:
The correct answer is option E.
Explanation:
Structures for the reactants and products are given in an aimage ;
Number of double bonds in oxygen gas molecule = 1
Number of double bonds in nitro dioxide gas molecule = 1
Number of single bond in in nitro dioxide gas molecule = 1
Number of triple bonds in nitrogen gas molecule = 1

![\Delta H=[2 mol\times \Delta H_{f,NO_2}]-[1 mol\times \Delta H_{f,N_2}-2 mol\times \Delta H_{f,O_2}]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B2%20mol%5Ctimes%20%5CDelta%20H_%7Bf%2CNO_2%7D%5D-%5B1%20mol%5Ctimes%20%5CDelta%20H_%7Bf%2CN_2%7D-2%20mol%5Ctimes%20%5CDelta%20H_%7Bf%2CO_2%7D%5D)

(pure element)
(pure element )

The enthalpy of the given reaction is 15.86 kcal.
Answer:
How can I tell if a chemical reaction is occurring? A chemical reaction is usually accompanied by easily observed physical effects, such as the emission of heat and light, the formation of a precipitate, the evolution of gas, or a color change.
Explanation:
Answer:
A. He arranged the first periodic table.
Explanation:
Answer:
the ansnwer is c mf kf n dsj njnr kgjrk nj ee h ewfkjhnf ewjn fnkwfnjnfnfunf
Explanation:
because is sooo goood
They have the same number of electrons in their outer shells. Elements in the same group often share similar chemical properties because the outer electrons generally determine a lot of their properties