Henlo!
Bohr's model was unable to calculate or it required precise information about position of an electron and its velocity. It is very difficult to calculate velocity and position of an electron at the same time because electron i too small to see and may only be observed if peturbed, for example we could hit the electron with another particle such as photon or an electron, or we could apply electric or magnetic field to the electron. This will inevitably change the position of the elctron or its velocity and direction. Heisenberg aid that more precisely we can define the position of an electron, the less certainity we are able to define its velocity and vice versa.
In short, first option is correct one
In Chemistry, to better determine the position of a certain electron, quantum numbers are used. The four quantum numbers are n, l, m and s. In the given above of n= 4, the principal quantum number is 4 and this represents the overall relative energy in the orbital. This means that we are to find the maximum number of electrons in fourth main energy level and the answer is 32.
Answer:
7 to 4 (higher
)
5 to 3
3 to 2
4 to 2 (lower
)
Explanation:
We can use the Rydberg formula which relates the wavelength of the photon emissions to the principle quantum numbers involved in the transition:

with
final n, and
initial n
evaluating for each transition:
7 to 4 
5 to 3 
4 to 2 
3 to 2 
Note that the above formula is written for
, so lower
value obtained involves higher
.
So we should order from lower to higher 
7 to 4 (higher
)
5 to 3
3 to 2
4 to 2 (lower
)
Note: Take into account that longer wavelength involves lower energy (
).
Answer:
the answer is D my friend
Answer:
Methylethanoate with the molecular formula; CH₃- CO₂-CH₃
Explanation:
The Molecular formula of the given compound CH₃ - CH₂- COOH is called propanoic acid. Molecular formula expresses the exact number and kinds of atoms of the elements present in the molecule of a compound. Propanoic acid is the second compound in the group of carboxylic acids. The certain similarities these carboxylic acids posses is due to the functional group - COOH. Functional groups is the categorization of atoms within molecules that possess their own certain characteristics which makes them distinct from other functional groups.
The molecular formula which represents an isomer of the given compound CH₃ - CH₂- COOH is called Methylethanoate with the molecular formula; CH₃- CO₂-CH₃
Isomers are existence of two or more compounds with the same exact molecular formula but with different molecular structures due to the difference in the arrangement of atoms or spatial orientation of atoms.