Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Q. What do you understand by dissolved oxygen in water? How does it create trouble in boiler? Give chemical methods with suitable reactions to remove it from the water.
Ans.
Presence of dissolved oxygen: At room temperature about 8 ppm of dissolved oxygen is present in water. Oxygen enters the boiler through raw make up water. When water containing the free gas is evolved under prevailing high temperature of boiler and attacks the boiler material.
2Fe + 2H2O + O2 = 2Fe (OH) 2
4Fe (OH) 2 + O2 + 2H2O = 2[Fe2O3.2H2O]
Removal of dissolved oxygen:
1. Chemical means: Oxygen can be removed by adding calculated amounts of certain chemicals such as Na2SO3, Na2S and N2H4.
Na2SO3 + O2 = 2Na2SO4
Na2S + 2O2 = Na2SO4
However, the sodium sulphate so formed may decompose in high pressure to form H2SO4. Hydrazine (N2H4) is found to be an ideal compound for removing dissolved oxygen since the products are water and nitrogen gas
N2H4 + O2 = N2 + 2H2o
Mechanical means: It works on Henry's law and Dalton's law. Solubility of gas is directly proportional to pressure. Mechanical desecrator is used
LIGAND FIELD THEORY The five d orbitals with distinct values of the magnetic quantum number (m) have the similar energy in a free atom or ion. In any compound they interact
USE THE KINETIC PARTICLE THEORY TO EXPLAIN THE EXISTENCE OF THE DIFFERENT STATES OF MATTER
Reaction Intermediates Short lived fragments that are known as reaction intermediates result from homolytic and heterolytic bond fission. The significant reaction substances ar
Explain Resonance effects Resonance effects: The application of the resonance effect for predicting the relative rates of acid-catalyzed ester and amide hydrolyses is exactly
Which of the following is not true in Rutherford's nuclear model of atom: (1) Protons and neutrons are present inside nucleus (2) Volume of nucleus is very small as compared
(a) Given the values below, calculate the concentration of benzoyl peroxide required to prepare polystyrene with a number average molar mass of 400,000 by bulk free radical polymer
Q. What are the Chemical Properties of Halogens? Ans. he halogens have 7 valence electrons in their outermost shell. Note that 7 is one electron short of the octet.
Q. Describe Subatomic Particles and the Nuclear Atom? One of the most significant results of Dalton's theory was that it generally persuaded scientists that atoms exist. As a r
what is alchemy
Aufbau principle is not satisfied by: (1) Cr and Cl (2) Cu and Ag (3) Cr and Mg (4) Cu and Na Ans: Cu and Ag
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd