The density of water at room temperature is 0.9970 g cm^-3. How many pounds does the water in a full 5 gallon pail weigh?

The density of water at room temperature is given as
0.9970 g/cm^3.

We have to determine the mass of 5 gallons
of water in terms of pounds.

The unit conversions involved
here are from gallons to liters, from grams to pounds and from cm^3 to
liters.

1 gallon = 3.78541178 liters, 1 g = 0.00220462262
pounds and 1 cm^3 = 0.001 l.

The density of water in g/l =
0.9970*10^3 g/l

5 gallons = 18.927
l

The mass of 18.927 l in grams is 18.927*997 = 18870.27
g

The mass in pounds is 41.60
pounds.

The 5 gallons of water weigh 41.60
pounds.