What does the 2 represent inH2

dihydrogen monoxide. The 2 is the subscript for H symbolises the presence of 2 Hydrogen atoms.

Explanation:

If we want to represent two atoms of hydrogen, instead of writing H H, we write H2.

Explanation:

The subscript "2" means that two atoms of the element hydrogen have joined together to form a molecule. A subscript is only used when more than one atom is being represented. ... Some more common molecules and their chemical formula.

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 :

the answer to your question is c