Answer:
11.8.4 Distillation Columns
Distillation columns present a hazard in that they contain large inventories of flammable boiling liquid, usually under pressure. There are a number of situations which may lead to loss of containment of this liquid.
The conditions of operation of the equipment associated with the distillation column, particularly the reboiler and bottoms pump, are severe, so that failure is more probable.
The reduction of hazard in distillation columns by the limitation of inventory has been discussed above. A distillation column has a large input of heat at the reboiler and a large output at the condenser. If cooling at the condenser is lost, the column may suffer overpressure. It is necessary to protect against this by higher pressure design, relief valves, or HIPS. On the other hand, loss of steam at the reboiler can cause underpressure in the column. On columns operating at or near atmospheric pressure, full vacuum design, vacuum breakers, or inert gas injection is needed for protection. Deposition of flammable materials on packing surfaces has led to many fires on opening of distillation column for maintenance.
Another hazard is overpressure due to heat radiation from fire. Again pressure relief devices are required to provide protection.
The protection of distillation columns is one of the topics treated in detail in codes for pressure relief such as APIRP 521. Likewise, it is one of the principal applications of trip systems.
Another quite different hazard in a distillation column is the ingress of water. The rapid expansion of the water as it flashes to steam can create very damaging overpressures.
Answer:
5446.8 J
Explanation:
From the question given above, the following data were obtained:
Mass (M) = 50 g
Initial temperature (T₁) = 70 °C
Final temperature (T₂) = 192.4 °C
Specific heat capacity (C) = 0.89 J/gºC
Heat (Q) required =?
Next, we shall determine the change in the temperature. This can be obtained as follow:
Initial temperature (T₁) = 70 °C
Final temperature (T₂) = 192.4 °C
Change in temperature (ΔT) =?
ΔT = T₂ – T₁
ΔT = 192.4 – 70
ΔT = 122.4 °C
Finally, we shall determine the heat required to heat up the block of aluminum as follow:
Mass (M) = 50 g
Specific heat capacity (C) = 0.89 J/gºC
Change in temperature (ΔT) = 122.4 °C
Heat (Q) required =?
Q = MCΔT
Q = 50 × 0.89 × 122.4
Q = 5446.8 J
Thus, the heat required to heat up the block of aluminum is 5446.8 J
Answer:
B. Ionic Compound
Explanation:
An ionic compound is that compound which contains a positively charged ion called CATION and a negatively charged ion called ANION. The cation loses or transfers electrons to the anion, hence, making the former (cation) positive and the latter (anion) negative.
A polyatomic ion is an ion that contains more than one type of atom e.g OH-, NO3²-, CO3²- etc. A polyatomic ion usually has an overall charge formed from the charges of the individual atoms that makes it up. For example, in OH-, the overall charge is -1.
Since a polyatomic ion can have an overall positive or negative charge, it must enter a reaction with another ion that complements it i.e. a negative polyatomic ion will react with a positive ion to neutralize its charge. Hence, this forms an IONIC COMPOUND. This is why most compounds with polyatomic ions are IONIC COMPOUNDS.
For example, CaCO3 is an ionic compound formed when Ca²+ (cation) reacts with the polyatomic anion: CO3²-
Answer:
Explanation:
The physical methods of separating mixtures are used in sorting a mixture of substances.
It requires no chemical changes occurring between their components and parts in any significant way.
Examples are:
- Decantation
- Filtration
- Sublimation
- Magnetism
- Centrifugation
The methods simply relies on the physical properties of matter.
Answer:
The reaction type is double displacement