Hess's law can be used to calculate reaction enthalpies for hypothetical processes that can't be carried out in the laboratory. set up a hess's law cycle that will let you calculate δ h∘ for the conversion of methane to ethylene: 2ch4(g) → c2h4(g)+2h2(g) you can use the following information: 2c2h6(g)ch4(g)c2h4(g)h2o(l),+++7o2( g)2o2(g)h2(g)→→→4co2(g)co2(g)c2h6(g ),++6h2o(l),2h2o(l),δh∘=−3120.8 kjδh∘=−890.3 kjδh∘=−136.3 kjδh∘f=−285.8 kj/mol
express your answer to four significant figures and include the appropriate units.

Since the gas in your graduated cylinder is a mixture of butane and water vapor, you must determine the partial pressure of the butane, pbutane, alone. to do this, consult a reference and record the partial pressure of the water vapor, pwater, at the temperature you recorded. use the following formula to compute the partial pressure of the butane. pbutane = atmosphere - pwater use the following combined gas law formula and compute the volume that the butane sample will occupy at stp. (hint: convert both temperatures to kelvin.) pbutane x voriginal = pstandard x vfinal troom tstandard use the following ratio and proportion formula to determine the mass of butane needed to occupy a volume of 22.4 l at stp. grams of butane you used “x” grams of butane ml of butane corrected to stp = 22,400 ml compute the theoretical molar mass of butane based on its formula and the atomic masses on the periodic table. compare your experimental results from #3 to the theoretical value of #4, computing a percent error of your findings using this formula: % error = measured value - accepted value x 100 accepted value use the following ratio and proportion formula to determine the mass of butane needed to occupy a volume of 22.4 l at stp. need asap

What is the percentage composition of carbon in the compound ch4

Which of the following are correct values for the ideal gas laws constant r