CHEMICAL ENGINEERING QUESTIONS
AND VERIFIED ANSWERS|100%
CORRECT|GRADE A+
Describe the difference between Chemists and Chemical Engineers - ANSWER Chemists are on a smaller
scale, do more research, are innovative, document reactions, and develop new compounds. Chemical
Engineers work with existing materials, are on a larger scale, and focus on storage/transport and plant
design/operation. Both take chemistry, bust chemists take more detailed courses.
What is Chemistry? - ANSWER The scientific study of materials, their composition and structure,
properties, interactions, and changes they undergo.
What are Thermodynamics? - ANSWER The study of work, energy, and efficiency in large-scale systems.
Zeroth Law - ANSWER Thermal Equilibrium
First Law - ANSWER Law of conservation of energy
Second Law - ANSWER Energy will naturally disperse
Entropy - ANSWER The tendency of all energy and matter to seek a state of uniformity
Third Law - ANSWER The colder a substance gets, the less its atoms move
What are Fluid Dynamics? - ANSWER Study of fluid flow
Turbulent Flow - ANSWER Velocity fluctuations; highly disordered
Contains swirls of water called "eddies"
Fluid particles flow in many directions with no observable paths
As turbulent flow increases, so does energy needed to move it
, Inertial forces dominate
Laminar Flow - ANSWER Has no disruption between layers of fluid
Smooth streamlines, highly ordered
Little to no mixing; particles flow in a straight path
Viscous forces dominate
What is Fluid Flow characterized by? - ANSWER Reynolds Number
RN = Density x Velocity x Diameter of Pipe / Dynamic Viscosity
Under 2,500 => Laminar
Over 10,000 => Turbulence
Mass Balance - ANSWER States that matter cannot be created or destroyed and must be constant in a
closed loop.
Amount of material that exists prior to chemical reaction is equal to the amount of material after the
reaction.
Differential Mass Balance - ANSWER Measurement taken at the same point over time.
Applied to a continuous process.
Should always be the same.
Each term in a differential balance equation represents a process stream and the mass flow rate of the
chemical(s) in that stream.
Integral Mass Balance - ANSWER Are taken at 2 different points to show what is happening between 1
point and another.
Typically taken at beginning and end of process.
Each term in an integral balance represents a process stream and the mass of the chemical(s) in that
stream.
Fluid Flow Rate, Pressure, and Temperature - ANSWER What are crucial to measure?
AND VERIFIED ANSWERS|100%
CORRECT|GRADE A+
Describe the difference between Chemists and Chemical Engineers - ANSWER Chemists are on a smaller
scale, do more research, are innovative, document reactions, and develop new compounds. Chemical
Engineers work with existing materials, are on a larger scale, and focus on storage/transport and plant
design/operation. Both take chemistry, bust chemists take more detailed courses.
What is Chemistry? - ANSWER The scientific study of materials, their composition and structure,
properties, interactions, and changes they undergo.
What are Thermodynamics? - ANSWER The study of work, energy, and efficiency in large-scale systems.
Zeroth Law - ANSWER Thermal Equilibrium
First Law - ANSWER Law of conservation of energy
Second Law - ANSWER Energy will naturally disperse
Entropy - ANSWER The tendency of all energy and matter to seek a state of uniformity
Third Law - ANSWER The colder a substance gets, the less its atoms move
What are Fluid Dynamics? - ANSWER Study of fluid flow
Turbulent Flow - ANSWER Velocity fluctuations; highly disordered
Contains swirls of water called "eddies"
Fluid particles flow in many directions with no observable paths
As turbulent flow increases, so does energy needed to move it
, Inertial forces dominate
Laminar Flow - ANSWER Has no disruption between layers of fluid
Smooth streamlines, highly ordered
Little to no mixing; particles flow in a straight path
Viscous forces dominate
What is Fluid Flow characterized by? - ANSWER Reynolds Number
RN = Density x Velocity x Diameter of Pipe / Dynamic Viscosity
Under 2,500 => Laminar
Over 10,000 => Turbulence
Mass Balance - ANSWER States that matter cannot be created or destroyed and must be constant in a
closed loop.
Amount of material that exists prior to chemical reaction is equal to the amount of material after the
reaction.
Differential Mass Balance - ANSWER Measurement taken at the same point over time.
Applied to a continuous process.
Should always be the same.
Each term in a differential balance equation represents a process stream and the mass flow rate of the
chemical(s) in that stream.
Integral Mass Balance - ANSWER Are taken at 2 different points to show what is happening between 1
point and another.
Typically taken at beginning and end of process.
Each term in an integral balance represents a process stream and the mass of the chemical(s) in that
stream.
Fluid Flow Rate, Pressure, and Temperature - ANSWER What are crucial to measure?
