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:
The Coriolis effect
Explanation:
The Coriolis effect is the effect that makes tornados, water spouts, and are often seen in storms. They make water curve and rotate as well as the wind And current.
Answer:
Option (c).
Explanation:
Cellulose is one of the most important carbohydrate of the plant that provide structural framework to the plant cells. Cellulose is made of the monomer of the glucose that are linked through the beta glycosidic linkages.
Although cellulose contains large number of glucose but it cannot be used as the nutrient source for humans. Humans and other vertebrates lacks the enzyme cellulase that is required for the digestion of cellulose. Cellulose cannot be broken down in the human body.
Thus, the correct answer is option (c).
Answer:
B
Explanation:
The sun can be dangerous but it also helps our Earth in a lot of ways
Fluorine is a nonmetal and as such it would need to take in or obtain an electron from a metal to have a stable octet, or full number of 8 electrons in its valence shell. Thus due to the indifference of electrons and protons it becomes an anion, a negatively charged ion.