Find value of Q from following equations.

(i) $\mathrm{C}_{(\mathrm{s})}+\mathrm{O}_{2(\mathrm{~g})} \longrightarrow \mathrm{CO}_{2(\mathrm{~g})} \Delta \mathrm{H}=\mathrm{QkJ}$

(ii) $\mathrm{C}_{(\mathrm{s})}+\frac{1}{2} \mathrm{O}_{2(8)} \longrightarrow \mathrm{CO}_{2(8)} \Delta \mathrm{H}=-\mathrm{x} \mathrm{kJ}$

(iii) $\mathrm{C}_{(\mathrm{s})}+\frac{1}{2} \mathrm{O}_{2(\mathrm{~s})} \longrightarrow \mathrm{CO}_{2(\mathrm{~g})} \Delta \mathrm{H}=-\mathrm{ykJ}$

"A given compound always contains the same proportion of elements" is a statement of -

Identify the correct decreasing order of thermal stability from following.

What is the number of moles of N atoms and number of moles of O atoms respectively present in one mole of uracil?