A spacecraft is fueled using hydrazine (N2H4; molecular weight of 32 grams per mole [g/mol]) and carries 1640 kilograms [kg] of fuel. On a mission to orbit a planet, the fuel will first be warmed from −186 degrees Fahrenheit [°F] to 78 degrees Fahrenheit [°F] before being used after the long space flight to reach the planet. The specific heat capacity of hydrazine is 0.099 kilojoules per mole kelvin [kJ/(mol K)]. If there is 300 watts [W] of power available to heat the fuel, how long will the heating process take in units of hours [h]?

The value is

Explanation:

From the question we are told that

The molar mass of hydrazine is

The initial temperature is

The final temperature is

The specific heat capacity is

The power available is

The mass of the fuel is

Generally the number of moles of hydrazine present is

=>

=>

Generally the quantity of heat energy needed is mathematically represented as

=>

=>

Generally the time taken is mathematically represented as

=>

=> t = 2480505.6377 s

Converting to hours

=>

what are the statements? x

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.