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<span>the rapid expansion of matter from a state of extremely high density and temperature that according to current cosmological theories marked the origin of the universe.</span>
Answer:
Option A, The pH of the solution is 2.7 and the solution is acidic
Explanation:
As we know,
pH = - log [H3O+]
Substituting the given values, we get
pH = - log [2.1 x 10-3 M]
pH = - (-2.678)
pH = 2.678 or 2.7
The solution is acidic as pH value is less than 7
Hence, option A is correct
I don't know this article, but I do know some major changes: first, the change from the plum pudding model (no nucleus, just electrons) to the gold foil experiment, which had Rutherford shoot alpha particles at a sheet of gold only to find them rebounding, proving the existence of a positively charged mass, i.e a nucleus, in the atom. However, this changed again when Bohr realized that the negatively charged electrons should be attracted to the positively charged center, so that there must be something else inside the nucleus.
Answer:
The word radon is derived from radium, of which radon is gas. Early in its discovery it was also called radium emanation and niton, which comes from the Latin nitens, Since 1923, however, it has been called radon.
