For the very last question you would first divide 8,900 by 12 and the number you get will be the answer. You should get 741.66
Answer is (4) - Pb.
According to the reactivity series of elements
- the elements which are above the hydrogen are more reactive than hydrogen.
- the elements which are below the hydrogen are less reactive than hydrogen.
Among the given choices, only Pb is placed above the hydrogen in the reactivity series and rest are below the hydrogen.
Hence, Pb is more active than hydrogen.
Answer:
Limitations of Rutherford Atomic Model
Although the Rutherford atomic model was based on experimental observations it failed to explain certain things. Rutherford proposed that the electrons revolve around the nucleus in fixed paths called orbits. ... Ultimately the electrons would collapse in the nucleus.
B. When scientific understanding changes.
