Moles of N2O5 = moles of NO2 * ( 2 moles of N2O5 / 4 moles of NO2
The answer is (2) A bond is formed and energy is released. The left side of equation is I atom and the right side of equation is I2 molecule. So the bond is formed between I atom to form I2 molecule. And forming bond will release energy while breaking bond will absorb energy.
<span>The vaporization of br2 from liquid to gas state requires 7.4 k/cal /mol.</span>
An element with 8 valence electrons is Neon (Ne).
Ps: Any element under group 18 has 8 valence electrons except for Helium (He).