What are some ways you can determine a chemical change has occured

1. Color changes.

The Statue of Liberty, though known for its green color, was originally covered in a layer of copper. After a redox (reduction-oxidation reaction) the color changed due to a chemical change.

2. Gas Production

3. Light Produced

Light sticks work as the result of a chemical reaction between hydrogen peroxide and phenol oxalate ester.

4. Temperature Changes

5. Volume Change

answer: the value of enthalpy change will be -152.80 kj.

solution:

pressure = 1atm , temperature = = 298 k

given that pressure and temperature are same in both gases , the number of moles of both gases can be determined by the ideal gas equation.

according to reaction 3 moles no are reacting with 1 mol of ,then 0.49 mol of no will react with moles of ozone that is 0.16 moles of ozone. since, no is limiting reagent and is an excessive reagent.

enthalpy change for the reaction between the given volumes of the gases is :