Question

Q3) Answer by “true” or “false” to the following statements:
1. dry basis: All the gases resulting from combustion process including the water vapor.
2. Theoretical air (or theoretical oxygen): The minimum amount of air (or oxygen) required to
be brought into the process for complete combustion
3. The limiting material comes out together with, or perhaps separately from, the product, and
sometimes can be used again.
4. The extent of reaction, ξ, is based on a particular stoichiometric equation, and denotes how
much reaction occurs
5. Open Systems mean that material neither enters nor leaves the vessel
Chemical engineering principles
Within 20 minutes

Answer 1

Q3)

1. Dry basis means the compositional analysis of all the product gases from a combustion process except water vapor.

So, Statement 1 is false.

2. Theoritical air means the stiochiometric air required for complete combustion of the fuel. That air amount is the minimum possible amount of air required to run the complete combustion.

So, statement 2 is true.

3. The limiting reactant in a reaction is the reactant which is present in stoichiometric amount, where rest reactants are present in excess amount. So, the limiting reactant is completely consumed by the process, whereas the other reactants remains in some excess amount. That excess amount comes out with product and can be separated for a recycle stream.

So, statement 3 is false.

4. The extent of reaction = number of moles of a reactant reacts / stoichiometric coefficient of that reactant.

As, extent of reaction is proportional to the number of moles reacted, extent can also denote the progress of reaction or how much reaction occured.

So, statement 4 is true.

5. In thermodynamics there are 3 basic systems.

Isolated system = no mass transfer, and no energy transfer.

Closed system = no mass transfer, but energy transfer can occur.

Open system = both mass transfer and energy transfer can occur.

So, statement 5 is false.