"NO" is the one among the following choices given in the question that has an incomplete <span>octet in the Lewis structure. The correct option among all the options that are given in the question is the fifth option or the last option or option "E". I hope that this is the answer that has come to your help.</span>
Explanation:
Water can be purified from through...
Filtration - This involves the use of filter paper to remove solid objects found in water.
Boiling - This involves keeping water at 100 deg celcius for a while through application of heat and this kills microorganisms in the water.
Addition of alum - Alum causes very fine and small particles that are suspending in water to stick together making them large enough to be removed through filtration.
Chemicals used in water treatment...
Chlorine - Chlorine is used to kill bacteria, viruses and other disease causing pathogens found in water
That's all I know...
- is a natural fibre
- has low elasticity
- is wrinkle free.
Answer:
The absorption and strength of the H-beta lines change with the temperature of the stellar surface, and because of this, one can find the temperature of the star from their absorption lines and strength. To better comprehend, let us look into the concept of the atom's atomic structure.
Atoms possess distinct energy levels and these levels of energy are constant, that is, the temperature has no influence on it. However, temperature possesses an influence on the electron numbers found within these levels of energy. Therefore, to generate an absorption line of hydrogen in the electromagnetic spectrum's visible band, the electrons are required to be present in the second energy level, that is when it captivates a photon.
Therefore, after captivating the photons the electrons jump from level 2 to level 4, which shows that there is an increase in the stellar surface temperature and at the same time one can witness a decline in the strength of the H-beta lines. In case, if the temperature of the surface increases too much, then one will witness no attachment of electron with the hydrogen atom and thus no H lines, and if the temperature of the surface becomes too low, then the electrons will stay in the ground state and no formation of H lines will take place in that condition too.
Hence, to generate a very robust H line, after captivating photons the majority of the electrons are required to stay in the second energy level.
Answer:
7.5 sec.
Explanation:
A = A₀e⁻^kt => k = ln(A/A₀)/-t => ln(6.25/100)/-30s = 0.0924 s⁻¹
k·t₀.₅=0.693 => t₀.₅=0.693/k = (0.693/0.0924)s = 7.5 s