Which substance has the highest density at room temperature? a.
Hydrogen
c.
Water
b.
Oxygen
d.
They are all the same

The correct answer is Water

Water is the most dense compound of all the mentioned ones. Hydrogen and Oxygen are gasses.

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 :

a corroding iron, if that's one of your choices