Light and sound aren't matter because Photons have no mass.
No..............................
Answer:
- 13,150.6kJ
Explanation:
CH4 + 2 O2 ------> CO2 + 2 H2O ΔH= – 890 kJ
The ΔH is enthalpy change of combustion , which is the heat is either absorbed or released by the combustion of one mole of a substance.
ΔH=−890 kJ/mol (released in the combustion of one mole of methane)
using the molar mass (in grams )of methane to get moles of sample
(237g × 1 mole of CH4)/16.04g=14.776 moles of CH4
Since 1 mole produces 890 kJ of heat upon combustion, then 14.776 moles will produce
ΔH = 14.776moles of CH4 × 890kJ/1mole of CH4
=13,150.6kJ
Therefore ΔH = - 13,150.6kJ
Answer:
Pure Substance. A sample of matter, either a single element or a single compound, that has definite chemical and physical properties. Element. A pure substance that cannot be broken down into other substances by chemical or physical means.
Explanation:
Sorry if it's wrong!!!!!!!
The combustion reaction is as expressed,
CxHy + O2 --> CO2 + H2O
The mass fraction of carbon in CO2 is 3/11. Hence,
mass of C in CO2 = (3.14 g)(3/11) = 0.86 g C.
Given that we have 1 g of the hydrocarbon, the mass of H is equal to 0.14 g.
moles of C = 0.86 g C / 12 g = 0.0713
moles of H = 0.14 g H / 1 g = 0.14
The empirical formula for the hydrocarbon is therefore, CH₂.
