Answer:

Explanation:
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In this case, since we are considering an gas, which can be considered as idea, we can write the ideal gas equation in order to write it in terms of density rather than moles and volume:

Whereas MM is the molar mass of the gas. Now, since we can identify the initial and final states, we can cancel out R and MM since they remain the same:

It means we can compute the final density as shown below:

Now, we plug in to obtain:

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B is the answer to your question
Answer:
C). The Bohr-Rutherford model
Explanation:
The 'Bohr-Rutherford model' of the atom failed to elaborate on the attraction between some substances. It essentially targeted hydrogen atoms and failed to explain its stability across multi-electrons. The nature and processes of the chemical reactions remained unillustrated and thus, this is the key drawback of this model. Thus, <u>option C</u> is the correct answer.
Answer:
2.881x10^23 atoms
Explanation:
From the studies of Avogadro's hypothesis, we discovered that 1mole of any substance contains 6.02x10^23 atoms.
Therefore 1mole of Fe contains 6.02x10^23 atoms.
Molar Mass of Fe = 56g/mol
56g of Fe contains 6.02x10^23 atoms.
Therefore, 26.8g of Fe will contain = (26.8x6.02x10^23) / 56 = 2.881x10^23 atoms