if the combustion of oil yields 4.0x10^4 kj/kg what mass of oil must be burned to yield the number of joules in part b? the answer i got in part b was 7.70 x10^11 J and that it right. for this problem i divided the answer i got 7.70x10^11 by 4.0x10^4 and changed the 4.0x10^4 to joules and then multiplied by 1 kj but i didn't get the right answer.
To determine the mass of oil that needs to be burned to yield a given number of joules, follow the steps below:
1. Start with the desired number of joules: 7.70 x 10^11 J
2. Divide this value by the heat yield per kilogram (4.0 x 10^4 kJ/kg) to convert from joules to kilograms:
7.70 x 10^11 J / (4.0 x 10^4 kJ/kg) = (7.70 x 10^11 J) / (4.0 x 10^4 J/kg)
Both the numerator and denominator are expressed in joules, so the units cancel out, leaving:
= (7.70 x 10^11) / (4.0 x 10^4) kg
3. Simplify the expression and calculate the result:
= 1.925 x 10^7 kg
So, you would need to burn approximately 1.925 x 10^7 kg of oil to yield 7.70 x 10^11 J of energy.
To determine the mass of oil that must be burned to yield a specific amount of energy, you need to use the equation:
Energy = Mass * Heat of Combustion
In this case, you have the energy in joules (7.70 x 10^11 J) and the heat of combustion in kilojoules per kilogram (4.0 x 10^4 kJ/kg).
Here's how you can correctly calculate the mass of oil:
1. Convert the heat of combustion from kilojoules to joules by multiplying it by 1000 since 1 kilojoule is equal to 1000 joules. So, 4.0 x 10^4 kJ/kg becomes 4.0 x 10^7 J/kg.
2. Rearrange the equation to solve for mass: Mass = Energy / Heat of Combustion
Mass = (7.70 x 10^11 J) / (4.0 x 10^7 J/kg)
3. Cancel out the unit "J" in the denominator with "J" in the numerator, which leaves you with kilograms (kg) as the unit for mass.
4. Calculate the mass by dividing the energy by the heat of combustion:
Mass = (7.70 x 10^11) / (4.0 x 10^7) kg
Mass = 19250 kg
Therefore, the mass of oil that must be burned to yield 7.70 x 10^11 J is 19250 kg.