Understanding Pure Substances and Thermodynamics Principles
Pure Substances
Heat Transfer Equations
Q1 = m * Cn * ΔT
m: mass of water
Cn: specific heat of ice
Q2 = m * Lf: heat of fusion (latent) for ice
Q3 = m * C * ΔTC: Heat sensible
C: 1 Kcal/Kg
Q4 = m * Lv: heat of vaporization (latent) for H2O
Lv: 540 Kcal/Kg
Lv: 970 BTU / LBM
Q5 = m * Cv * ΔT
Cv: 0.45 Kcal / Kg
Example Calculation
200 g of ice at -10 ºC to calculate the amount needed to transform 200 g of steam at 120 ºC. The external pressure is 760 mmHg. The specific heat of ice is 0.5 cal / g ºC and
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1) Bread Manufacturing
Understanding Combustion Emissions and Air Quality Impact
Combustion is a major source of air pollution emissions. The complete combustion of hydrocarbon fuel produces only CO2 and H2O as products, according to the following stoichiometry:
CH4 + 2 O2
CO2 + 2 H2O
a) Mass of air required for complete combustion of 500 kg of CH4, assuming O2 = 21% of air.
b) Mass of CO2 produced from the above combustion.
c) Calculate the mass of air required for combustion of 500 kg of benzene (C6H6).
a) Mass of O2 required =
Mass of air required = 2000/0.23 = 8696 kg
b) Mass
Read MoreEffective Management of Wastewater Treatment Plants
Treatment Plant Management
Wastewater treatment plants are two types of property: private and public.
The former seek to be the latest generation, high efficiency, so that the minimum operational costs, with highly qualified and understaffed personnel, highly automated systems with fast response to any eventuality, and ease of replacement and modernization.
The public type is subject to the availability of funds and therefore is not generally high in technology, and its efficiency is not high. Work
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Free Energy
Free energy is the thermodynamic quantity used to study biological processes and predict whether they are energetically favorable. It represents the energy capable of performing useful work under constant temperature and pressure. The sign of ΔG indicates the reaction’s behavior:
- ΔG < 0: The reaction is exergonic (energetically favorable), releasing free energy.
- ΔG > 0: The reaction is endergonic (energetically unfavorable), requiring free energy absorption.
- ΔG = 0: The system
Polymer and Ceramic Materials: Properties and Applications
To obtain a polymer in polymer chemistry, hundreds of thousands of monomer molecules are chemically bonded. This creates homopolymers. If the polymer chain is formed by the union of different monomers, copolymers are obtained. In polycondensation, chain growth occurs by chemical reaction between two functional groups, most often with the loss of a small molecule, such as water or hydrochloric acid. In polyaddition, chain growth occurs by continuous addition of the same type of small molecules that
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