Chem

Energy needed to keep a 75w bulb burning for 1 hour = 270kj Calculate energy neede to keep it burning for 3 hours?
In J and kcal?
I got the J: It is 270kj x 1000/1 x 3/1 = 810000=8.1 x 10^5J
But How Do I get the kcal?
Thank you

1. 1 cal = 4.184 J
1000 cal = 1 kcal.

posted by DrBob222

First Name

Similar Questions

1. chemistry

suppose a car operates so inefficently that only 16% of the thermal energy from burning fuel is converted to useful "wheel turning" (mechanical energy) how many kj of useful energy would be stored in a 20 gallon tank of
2. Chemistry

The amount of energy released by burning a fuel source, measured in energy per mass, is called the fuel value. If all the energy obtained from burning 1.30 pounds of methane (fuel value is 11.97 kcal/g) is used to heat 122.0 kg of
3. Chemistry

The amount of energy released by burning a fuel source, measured in energy per mass, is called the fuel value. If all the energy obtained from burning 1.28 pounds of methane (fuel value is 11.97 kcal/g) is used to heat 127.0 kg of
4. chemistry

The amount of energy released by burning a fuel source, measured in energy per mass, is called the fuel value. If all the energy obtained from burning 1.29 pounds of butane (fuel value is 10.85 kcal/g) is used to heat 122.5 kg of
5. Chemistry

The amount of energy released by burning a fuel source, measured in energy per mass, is called the fuel value. If all the energy obtained from burning 1.25 pounds of propane (fuel value is 11.09 kcal/g) is used to heat 123.0 kg of
6. Chemistry

The amount of energy released by burning a fuel source, measured in energy per mass, is called the fuel value. If all the energy obtained from burning 1.28 pounds of methane (fuel value is 11.97 kcal/g) is used to heat 127.0 kg of
7. Chemistry

The amount of energy released by burning a fuel source, measured in energy per mass, is called the fuel value. If all the energy obtained from burning 1.25 pounds of butane (fuel value is 10.85 kcal/g) is used to heat 120.0 kg of
8. Chemistry

The amount of energy released by burning a fuel source, measured in energy per mass, is called fuel value. If all the energy obtained from burning 1.3 pounds of butane (fuel value 10.85 kcal/g) is used to heat 122 kg of water at
9. Chemistry

Why are combustion reactions always exothermic? Is it just because it gives off heat? Thanks ahead of time Exothermic MEANS it gives off heat; therefore, I don't think that can be a reason. Think of wood burning. Magnesium strips
10. science-physics

Q1)which of these energy resources does not originate from the suns energy?:natural gas,oil,geothermal energy,coal Q2)the burning of fossil fuels does not release? potential energy,light energy,sound energy , heat energy?? Q3)at

More Similar Questions