1)Delta H=(Delta H of reactants)-(Delta H of products)
2)And we know CO have 3 bond CO and CO2 have 2 bond that each of them are 2 bond, please see the picture!
so lets answer it:

Answer:
1 molecule of oxygen has 2 atoms.
So 2,25 molecules of oxygen have 2 x 2,25 atoms.
2 x 2,25 = 4,5 atoms
There are 4,5 atoms in 2,25 molecules oxygen.
5.4 M = moles of solute / 1.50 L
<span>Multiply both sides by 1.50 L to isolate moles of solute on the right. </span>
<span>8.1 mol = moles of solute </span>
They have thier own group because because they have traits or metals and nonmetals