Answer is: the discovery of sub atomic particles like electrons.
J. J. Thomson discovered the electron in 1897.
His "plum pudding" model (1904) suggested: the electrons are embedded in the positive charge.
With this model, he abandoned his earlier hypothesis (the atom was composed of immaterial vortices).
J.J. Thomson placed two oppositely charged electric plates around the cathode ray. He did experiments using different metals as electrode materials and found that the properties of the cathode ray remained constant no matter what cathode material he used.
Tomson concluded that atoms are divisible and that the corpuscles are their building blocks (atoms are made up of smaller particles).
The answer should be B - Nitrogen Dioxide.
An organic compound that contains a carbonyl group with a hydroxyl group attached to it is an example of a (d) carboxylic acid.
Option D: Chromium would require the most energy to convert one mole of gaseous atoms into gaseous ions each carrying two positive charges.
<h3>What does the term “ionization energy” mean? </h3>
The ionization energy measures an element’s ability for participating in any chemical processes that calls up for the creation of ions or the donation of other electrons.
It is defined as the energy that any electron present in a gaseous atom or ion has in order to absorb so that it comes out of the influence of the nucleus and hence freely move
Ionization energy is also said as the minimum energy required to remove the most loosely bound electron that is present in an isolated gaseous atom or a positive ion or a molecule.
It can be easily connected to the type of chemical bonds that exist between the components in the compounds that they form.
<h3>Which element ionizes most energetically?</h3>
Helium, because it has the highest first ionization energy, whereas francium has one of the lowest.
To know more about Ionization energy visit:
brainly.com/question/1602374
#SPJ9
