Answer:
-800 kJ/mol
Explanation:
To solve the problem, we have to express the enthalpy of combustion (ΔHc) in kJ per mole (kJ/mol).
First, we have to calculate the moles of methane (CH₄) there are in 2.50 g of substance. For this, we divide the mass into the molecular weight Mw) of CH₄:
Mw(CH₄) = 12 g/mol C + (1 g/mol H x 4) = 16 g/mol
moles CH₄ = mass CH₄/Mw(CH₄)= 2.50 g/(16 g/mol) = 0.15625 mol CH₄
Now, we divide the heat released into the moles of CH₄ to obtain the enthalpy per mole of CH₄:
ΔHc = heat/mol CH₄ = 125 kJ/(0.15625 mol) = 800 kJ/mol
Therefore, the enthalpy of combustion of methane is -800 kJ/mol (the minus sign indicated that the heat is released).
Answer:
B. Better ways to recycle plastics
Explanation:
A chemist might choose to study better ways to recycle plastics because there may be certain types of chemicals that can disintegrate the plastic..
Answer:
1,500 mm
Explanation:
if 1 meter = 1000 mm, 0.5 meters is 500 mm, so 1.50 meters is 1,500 mm
Answer:
Explanation:
Hello,
In this case, is possible to infer that the thermal equilibrium is governed by the following relationship:
Thus, both iron's and water's heat capacities are: 0.444 and 4.18 J/g°C respectively, so one solves for the mass of water as shown below:
Best regards.
Answer:
It's nitrogen
Explanation:
cuz it has valence 3 and a diatomic gas at room temperature
