Just as a 'dozen' 12 of something, a 'mole' is about 6.02 *10^23 of something. in chemistry, we like to measure the number of atoms or molecules in moles. if one mole is equal to 6.02*10^23 atoms, and you have 7.00 * 10^23 atoms, then how many moles do you have?

6.02*10^23  to 7.00*10^23

You can just cancel out the 10^23 on both sides to make it easier.

6.02 to 7.00

in this case you will divide what you have (7) by what one is equal to (6.02)

7 / 6.02 = 1.16279069767 or approximately 1.163 or 1 and 49/301 or, for the most simplified fraction, 1 and 7/43

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 :