Calculate the mass of methane that must be burned to convert 318.0 g of water at 26.0°C into steam at 110.0°C.

Question

i cant find the specific heat of methane

Answer 1

You need the heat of combustion of methane. In order to solve the problem, you must raise the temperature of the water from 26.0C to 100C. 100 - 26 = 74degC

318gH2O x 1cal/g-deg x 74deg = 23,532cal

Next, boil the water. I assume the latent heat of vaporization is 512 cal/g.

318gH2O x 512 cal/gH2O = 162,816 cal

Finally, raise the temperature of the steam from 100C to 110.0C. I assume the heat capacity of steam is 0.6 cal/g.

318gH2O x 0.6cal/g = 191 cal

23,532cal + 162,816cal + 191cal = 186,539cal

To find the mass of methane, you must multiply 186,539cal by the cal/g heat of combustion of methane.

Answer 2

the warmth of combustion of methane is 802kJ/mol to transform water at 39C to steam at 110C. There are 3 steps. Heating water to 100C Vaporizing water to steam at 100C Heating steam to 110C Heating water to 100C q = mCdeltaT C = 4.184 J/gdegC q = (318g)(4.184 J/gdegC)(a hundred-39) = 81161 J Vaporizing water to steam at 100C q = mHvap (Hvap = warmth of vaporization at 100C = 2260 J/g) q = 318g(2260J/g) = 718,680 J Heating steam from 100C to 110C q = mCdeltaT C = 2.08 J/gdegC (warmth ability of steam is under liquid) q=318g(2.08 J/gdegC)(a hundred and ten-a hundred) =6614J finished capability replace interior the water is: 81161 J + 718,680 J + 6614 J = 806,455 J = 806.455 kJ each mole of methane combusted releases 802 kJ/mol capability. 806.455 kJ(a million mol CH4/802 kJ) = a million.0050 mol CH4 a million.0050 mol CH4(sixteen.0425 g CH4/mol CH4) = sixteen.12g CH4