Question

one principle shown on a pfd is the mass balance. this means that the mass entering a process equals the mass leaving, plus any accumulation. for example, if a plant processes 500 kg of feed and produces 300 kg of product and 100 kg of waste, 100 kg is unaccounted for. this \missing mass\ may be lost to leaks, spills, or measurement errors. identifying the missing mass is critical for safety, cost - control, and environmental protection. by understanding unit operations, pfds, and mass balance, technicians can ensure processes are safe, efficient, and reliable. multiple - choice questions for passage 2 16. unit operations are: a) building blocks of processes b) finished products c) waste materials d) only chemical reactions 17. what does a pump do? a) transfers heat b) moves liquids through pipes c) separates mixtures d) creates chemical reactions 18. what is the role of a heat exchanger? a) move feedstock through pipes b) transfer heat between fluids c) separate solids from liquids d) perform reactions 19. which equipment divides mixtures into parts? a) pump b) separator c) reactor d) heat exchanger 20. where do chemical reactions occur? a) separator b) pump c) reactor d) heat exchanger

Explanation:

1. Unit operations are the basic building - blocks of processes in chemical engineering and related fields.
2. A pump is a device that moves liquids through pipes by creating pressure differences.
3. The main function of a heat exchanger is to transfer heat between two or more fluids.
4. A separator is used to divide mixtures into their component parts based on differences in physical properties.
5. Chemical reactions occur in a reactor where reactants are brought together under appropriate conditions to form products.

Answer:

1. A. Building blocks of processes
2. b. Moves liquids through pipes
3. b. Transfer heat between fluids
4. b. Separator
5. c. Reactor