Using the following thermochemical data, what is the change in enthalpy for the following reaction: 3h2(g) + 2c(s) + ½o2(g) → c2h5oh(l) c2h5oh(l)+3o2(g)→2co2(g)+3h2o(l), δh = –1367 kj/mol c(s)+o2(g)→co2(g), δh = –393.5 kj h2(g)+½o2(g)→h2o(l), δh = –285.8 kj

The change in enthalpy for the formation of ethanol is -276.5 kJ/mol

Explanation:

The given reactions are:

The required reaction involves the formation of C2H5OH from C, H2 and O2:

This can be obtained by reversing reaction (1), multiplying equation (2) by 2, multiplying equation (3) by 3 and then adding the corresponding ΔH values

the ideal gas law equation is as follows

pv = nrt

where p - pressure

v - volume

n - number of moles

r - universal gas constant

t - temperature

so if the pressure, volume and temperature are already known

we are left with n and r

since r is the universal gas constant that has a known fixed value then r too is known

so we are left with 'n'

once we know temperature volume and pressure

we can find the number of moles of gas present using the ideal gas law equation

this is not my own answer, this is an answer for the same question by the user blahblahmali. i do not claim ownership of this account.