Answer:
Cultivated rice paddies
Drilling of natural deposits
Fossil fuel use
Burning of biomass
Landfills
Explanation:
The bulk of the methane released into the atmosphere are as a result of various human activities.
- Cultivated rice paddies are a known source of methane
- The drilling of natural deposits and their exploration can release some methane into the atmosphere
- Burning of fossil fuel and biomass is a source of methane
- Landfills produces methane as organic materials begins to decay.
B. Carbon dioxide bexause it is 96.5%
Answer:
The correct option is a.
Explanation:

125 kPa
125kpa - 2x 4x x
Total pressure after reaction = 176 kPa
125 kPa - 2x + 4x + x = 176 kPa
x = 17
125 kpa - 2x = 125 kPa - 2(17) = 91 kPa
Initial pressure of the dinitrogen pentoxide ,(at t=0) =
Final pressure of the dinitrogen pentoxide, (at t = t) = P = 91 kPa
The rate constant is = 



It will take 113 minutes for the total pressure to reach 176 kPa.
Answer:
The answer is: (a) positive; (b) negative.
Explanation:
The change in enthalpy (ΔH) of a reaction is the amount of energy absorbed or released during a chemical reaction carried out at constant pressure.
a) In an endothermic chemical reaction, heat energy is absorbed by the system from the surrounding. Therefore, the sign of enthalpy change for an endothermic process is positive, ΔH= positive.
b) In an exothermic chemical reaction, heat energy is released by the system into the surrounding. Therefore, the sign of enthalpy change for an exothermic process is negative, ΔH= negative.