Answer : The fuel value and the fuel density of pentane is, 49.09 kJ/g and 
respectively.
Explanation :
Fuel value : It is defined as the amount of energy released from the combustion of hydrocarbon fuels. The fuel value always in positive and in kilojoule per gram (kJ/g).
As we are given that:
Fuel value = 
Molar mass of pentane = 72 g/mol
Fuel value = 
Fuel value = 49.09 kJ/g
Now we have to calculate the fuel density of pentane.
Fuel density = Fuel value × Density
Fuel density = (49.09 kJ/g) × (0.626g/mL)
Fuel density = 30.73 kJ/mL =
Thus, the fuel density of pentane is
Boiling point<span> is the </span>temperature<span> at which the vapor pressure of the liquid equals the surrounding pressure.
Above boiling point point, liquid get converted into vapour.
Now, boiling point of water is 100 oC at room pressure. Room pressure is equal to 760 torr. Thus, at 100 oC, vapour pressure of water becomes equal to 760 torr.
Now, if external pressure is increased to 880 torr, more heat is to be supplied so that vapour pressure of water equals 880 torr.
So, at 880 torr, boiling point of water will be more than 100 oC. In present case, most like the boiling point of water is equal to 105 oC.
</span>
1 pound of coffee is said to yield 50 cups of coffee
So we need to find the pounds of coffee beans required to produce 250 cups
so if 50 cups need 1 pound of coffee beans
therefore 250 cups need - 1/50 x 250 = 5 pounds of coffee beans
since we have to find the amount of coffee beans needed in kg, we have to convert pounds to kg
1 pound = 0.45 kg
So if 1 pound is equivalent to 0.45 kg
then 5 pounds are equivalent to - 0.45 kg/pound x 5 pounds = 2.25 kg
therefore 2.25 kg of coffee beans are required
