Chemistry enthalpy/ entropy help!!

Question

Use Hess’s Law to determine the ΔH for the combustion of liquid methanol (CH3OH).

Using your answer from the previous question, how much energy will you get from burning 230.0 g of methanol in excess oxygen. (Hint: you must write a balanced reaction.)

 

 

 

Please show work so i know how to do it on my own! Thanks!

Answer 1

In order to answer this question I need to know what value you got for the "previous question". However, assuming you goth the same value of -675.96 kJ/mol of CH3OH you can use that value to determine the amount of heat released when 230.0 g of CH3OH is combusted as follows: (The molar mass of methanol is ~32.0 g/mol)

(675..96 kJ/ 1 mol CH3OH) (1 mol CH3OH/ 32.0 g CH3OH) (230.0 g CH3OH) = 4858 kJ ( to 4 sig figs)