Question

1. You have 0.95ft^3 aluminum(density=2700kg/m3,MW=26.98). Calculate the mass in kg, lbm, gmole and lbmole.

2. Assume there are 39 inches in a meter.What is the external surface area in the SI system of a sphere that is 9.0 inches in diameter? Determine the volume in cubic feet. (Note SI system: meters / kg / Newtons etc.)

3. If a US gallon has a volume of 0.134 ft3 and a human mouth has a volume of 0.950 in3, how many mouthfuls of water are required to fill a 7.5 US gallon can?

4. Convert the following:

a) 3.9cm/s to ft/min

b) 187 lbm ft/min2 to kg cm/s2

c) 55 ft3 to gallons

d) 920mg to ounces

e) 2lbm/ft.hr to g/cm.s

5. Water at 4C has a density of 1.0g/cm3 and a molecular weight of 18. What is the density in the following units:

a) kg/m3

b) lbm/ft3

c ) kmol/L

6. Do the following conversions:

a) 1.6 x 10^-2 g cm-1s-1 to lbm ft-1 s-1
b) What is the molecular weight of propionic acid (C2H5COOH).

c) How many kg are there in 10 lb mol of sodium hydroxide (NaOH)

Answer 1

1. 1 ft = 0.3m

0.95 ft3 = 0.95*0.3*0.3*0.3 m3

So, 0.95 ft3 = 0.02565 m3

Density = 2700 kg/m3

So, 1 m3 = 2700 kg

0.02565 m3 = 2700* 0.02565 = 69.255 kg

Now, 1 kg = 2.2 lbm

69.255 kg = 152.361 lbm

No of moles = Given Weight / Molecular Weight

Molecular Weight = 26.98 g/mole = 0.059 lbm/mole

No of moles = 69255 g / 26.98 g/mole = 2566.9 gmole

No of moles = 152.361 lbm / 0.059 lbm/mole = 2582.3 lbmmole

2. Surface Area of Sphere = 4*314*(radius)2

Diameter = 9 inches

39 in = 1 m

1 in = 1/39 m

9 in = 0.23 m

Surface area = 4*3.14*0.23*0.23 m2

Surface Area = 0.66 m2

Volume of sphere = 4/3 *3.14 * (radius)3

Volume = 0.051 m3

1 ft = 0.3 m

1 m = 3.33 ft

0.051 m3 = 1.88 ft3

Volume = 1.88 ft3

3. 1 US gallon = 0.134 ft3

1 Human Mouth = 0.95 in3

1 in = 0.08 ft

0.95 in3 = 4.8*10-4 ft3

So, 1 human mouth = 4.8*10-4 ft3

7.5 US gallon = 1.005 ft3

4.8*10-4 ft3 = 1 Human Mouth

1  ft3 = 2083.3 Human Mouth

1.005 ft3 = 2093.75 HUman Mouth

Thus, 2093.75 Human mouth are needed to fill 7.5 US gallon can.