A power station uses oil-fired boilers which are supplied with fuel from 4 cylindrical tanks, each with 12 m diameter and 11 m high. The calorific value of the oil is 38,039 kJ/kg and its relative density is 0.78. The output from the power station is 77 MW. Assuming the only 21% of the heat input is converted to into electrical energy output, how long will the boilers run (in days) on the oil in the tanks. Correct Answer: 4.7 ± 0.1

Q: A heat pump with a coefficient of performance of 1.8 supplies energy to a house at a rate of 75 MJ…

A: To find: electrical power used by the heat pump

Q: A heat engine is operating on a Carnot cycle and has a thermal efficiency of 50 percent. The waste…

A:

Q: A 650 MW steam power plant has an efficiency of 62%.it is cooled by rejecting heat to a nearby…

A: Given Data: Power produced, P=650 MW Efficiency, n=62 %

Q: The roofs of many homes in the United States are covered with photovoltaic (PV) solar cells that…

A:

Q: In a condenser, the vacuum gauge reads 66 čm of Hg while barometer reads 75 cm of Hg. The…

A: Given data,Condensor vacum reading=66 cm=660mmbarometer reads=75 cm=750 mmCorrected…

Q: Considering a steam generation plant, compare how temperature and pressure will affect the work done…

A: Introduction A steam power plant uses the heat energy released when coal is burned to produce…

Q: The gaseous coal is then burned in a gas turbine, and part of the waste heat from the exhaust gases…

A: The amount of energy spend is given by Etot=E·SPP The mass difference is given by ∆m=mcoal-mIGCC…

Q: A refrigeration system uses a water-cooled condenser for rejecting the waste heat. The system…

A: Write the expression for power input in terms of COP.

Q: A heating system that uses hot air has a total heating load of 509 thousand btuh. How much hot air…

A:

Q: Why some diesel vehicles have battery-driven heaters attached to the fuel tanks in order to be able…

A: Why diesel vehicles have battery-driven heaters attached to fuel tanks? An increase in viscosity…

Properties of Pure Substances

A substance with fixed chemical composition throughout is called a pure substance like water, air, and nitrogen. A pure substance does not have to be a single element or compound. A mixture of two or more phases of a pure substance is also a pure substance as long as the chemical composition is the same for all phases. These substances mainly have a constant/ uniform composition. The substances also have fixed boiling and melting points. A pure substance takes part in a chemical reaction to form predictable products.