Question

Tell 18 plz...... Fastly for brainliest answer

Answer 1

Answer : The correct option is, (2) -150 R

Explanation :

As we know that,

Heat released at constant pressure is known as enthalpy.

Heat released at constant volume is known as internal energy.

The given balanced chemical reaction is,

$\frac{1}{8}S_8(s)+\frac{3}{2}O_2(g)\rightarrow SO_3(g)$

Formula used :

$\Delta H=\Delta U+\Delta n_gRT$

or,

$\Delta H-\Delta U=\Delta n_gRT$

where,

$\Delta H$ = heat change at constant pressure

$\Delta U$ = heat change at constant volume

$\Delta n_g$ = change in moles = [(1mol)-(3/2mol)] = -0.5 mole

R = gas constant  

T = temperature = $27^oC=273+27=300K$

Now put all the given values in the above formula, we get:

$\Delta H-\Delta U=\Delta n_gRT$

$\Delta H-\Delta U=(-0.5mole)\times (300K)\times R$

$\Delta H-\Delta U=-150R$

Therefore, the difference between the heat change at constant pressure and volume will be, -150 R.