Recent content by Diamond101

Homework Statement A sample consisting of 1 mol of a diatomic perfect gas with Cv,m = 3/2 R is heated from 100 ºC to 300 ºC at constant pressure. Calculate ∆S for the system. Homework Equations Cv,m = 3/2 R The Attempt at a Solution Cpm=Cvm +r because we want cp right isobaric ∆S= Cp ln...

Homework Statement Calculate activation energy and pre exponential factor, i need help with the pre exponential factor Homework Equations Temperature °C -20 = 253 k -10= 263 0=273 10=283 20=293 Rate const. s-1 1.15 3.85 11.3 28.7 74.0 The Attempt at a Solution i already plotted the graph on...

hey i actually adds up the formation value for ethanol is -277.6 according to my chem3 textbook by burrows

actually i got Δcp= cp products -reactants= 43.3-24.44+0.5*29.36)= 3.18 kj/mol ΔHr 1000= ΔHr 298+ΔCpΔT -155.1*10^3 J-MOL * 3.18 JK-MOL *702 K =-155.1 *10^3 + 2232.36 = 152.9 KJ/MOL

And the equation was my lecture notes

actually i got Δcp= cp products -reactants= 43.3-24.44+0.5*29.36)= 3.18 kj/mol ΔHr 1000= ΔHr 298+ΔCpΔT -155.1*10^3 J-MOL * 3.18 JK-MOL *702 K =-155.1 *10^3 + 2232.36 = 152.9 KJ/MOL

I did compare the enthalpy of formation against the enthalpy of reaction . so the unit is Joule per kelvin?

OH IT WILL BE JOULES EVERYTHING ELSE CANCELS ?

i got -3582.14 KJ thank you for your assistance. (-1373+ (2 MOLES * 8.314* 298))

my mistake water is supposed to be a gas. so dh= -1373* 2 mol*8.314*298 k

because water isn't gas in its standard state ?

how? you didn't cater for h2o as a gas?

Change will be 2. so the relationship between enthalpy and internal energy is DH=DU=DNgasRT

Well 1 mole of c2h5OH and 3 molews of 02 , 2 Moles of CO2 and 3moles of h20 so the change is 1 mole 5- 4 moles

WAIT ITS A COMBUSTION REACTION