The contents of the freezer in a home refrigerator are maintained at 253.15 k (-20°c). the kitchen temperature is 293.15 k (20°c). if heat leaks amount to 125,000 w per day, and if e 0.08/kwh, estimate the yearly cost of running the refrigerator. assume a coefficient of perfor to 60% of the carnot value. ans. cost-s26718/yr mance equal

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.

the answer is c. nacl