I’d say A. They are theoretical in the fact that they have not been observed directly, but have been confirmed to exist through experimentation.
Answer:
B) Electrons are located in the cloud-like areas around the nucleus.
Explanation:
The quantum mechanical model of the atom does not consider the path through which an electron travels. It rather estimates the probability of where electrons can be found at each energy level.
The region of maximum probability of where an electron is located is sometimes called an electron cloud or orbital. Each orbital of an atom and the electrons accomodated are described completely by a set of four quantum numbers.
The answer is , C. Both the atomic mass and the atomic number increase from left to right .
Answer:
17.1195 grams of nitric acid are produced.
Explanation:

Moles of nitrogen dioxide :

According to reaction 3 moles of nitrogen dioxides gives 2 moles of nitric acid.
Then 0.5434 moles of nitrogen dioxides will give:
of nitric acid.
Mass of 0.3623 moles of nitric acid :

Theoretical yield = 22.8260 g
Experimental yield = ?


Experimental yield of nitric acid = 17.1195 g
The accepted model of the atom was changed.