Ch 3- Processes and Process Variables

Question 0

specific volume

Answer 0

volume occupied by a unit mass of the substance; inverse of density

Question 1

density

Answer 1

mass per unit volume

Question 2

specific gravity

Answer 2

ratio of density of a substance to a reference density at a specific condition; SG = ρ/ρ_ref

Question 3

The density of a substance can be used as a conversion factor to relate…

Answer 3

the mass and volume of a quantity of the substance

Question 4

If you are given the SG of a substance, multiply it by … to get the density of the substance in the same units

Answer 4

reference density; usually the density of water at 4 degrees centigrade

Question 5

What are the units of SG?

Answer 5

SG is dimensionless

Question 6

flow rate

Answer 6

the rate at which a material is transported through a process line

Question 7

What are the two ways that flow rate of a process can be expressed?

Answer 7

mass flow rate and volume flow rate

Question 8

How do you convert mass flow rate to volumetric flow rate and vice versa?

Answer 8

use the density of the material- ρ = m/V = mfr/vfr

Question 9

Name 2 commonly used flow meters

Answer 9

rotameter and orifice meter

Question 10

atomic weight

Answer 10

the mass of an atom on a scale that assigns 12C a mass of exactly 12

Question 11

molecular weight

Answer 11

the sum of the atomic weights of the atoms that constitute a molecule of the compound

Question 12

gram-mole or mil

Answer 12

the amount of a species whose mass in grams is numerically equal to its molecular weight

Question 13

How many molecules does one gram-mole contain?

Answer 13

6.02*10^23

Question 14

What can be used as a conversion factor to relate mass and the number of moles of a quantity of the substance?

Answer 14

molecular weight

Question 15

What relates mass flow rate to molar flow rate?

Answer 15

molecular weight

Question 16

mass fraction

Answer 16

x_A = mass of A/total mass

Question 17

mole fraction

Answer 17

y_A = moles of A/total miles

Question 18

percent by mass of A in terms of x_A

Answer 18

100x_A

Question 19

mole percent of A in terms of y_A

Answer 19

100y_A

Question 20

How do you convert a set of mass fractions to an equivalent set of mole fractions?

Answer 20

Assume as a basis of calculation a mass of the mixture (e.g. 100kg or 100lb), use mass fractions to calculate the mass of each component in the basis quantity and convert theses masses to moles. and take the ratio of the moles of each component to the total number of moles

Question 21

The mass of a species is the product of the mass fraction of that species and …

Answer 21

total mass (basis of 100g or some other value)

Question 22

The number of moles of a species is the mass of that species divided by…

Answer 22

the molecular weight of the species

Question 23

average molecular weight

Answer 23

ratio of the mass of a sample of the mixture to the number of moles of all species in the sample

Question 24

mass concentration

Answer 24

the mass of a component per unit volume

Question 25

molar concentration

Answer 25

the number of moles of a component per unit volume

Question 26

molarity

Answer 26

the value of the molar concentration of the solute expressed in gram-moles solute/liter solution

Question 27

What relates the mass or moles of a component in a sample of the mixture to the sample volume?

Answer 27

concentration of the component

Question 28

What relates mass or molar flow rate of a component of a continuous stream to the total volumetric flow rate of the stream?

Answer 28

concentration of the component