Chemistry 20 points
answer all the questions

Explanation:

Remark

First of all you have to identify what is happening. You make the following observations.

The solution in the test tube in a cold water bath is colorless.

As you add heat, the color changes from colorless to brown.

What you are told

N2O4 is colorless

NO2 is brownish red.

What you conclude

The reaction is endothermic. That means it requires heat to happen. An endothermic reaction is

A + Heat ===> B

So you have three possible correct answers

N2O4 + 14 kCal ===> 2NO2

N2O4 > 2NO2                    dH = 14 kCal

N2O4 > 2NO2 - 14  kCal

I can't read the last 4 equations.

Other answers

As the temperature increased, the N2O4 became less.

As the temperature increased, the products were favored. (color change)

The reaction is exothermic (gives off heat) when the reaction goes from

NO2 - Heat ===> N2O2