<u>Answer:</u> The fraction of atom's mass contributed by nucleus is 0.99
<u>Explanation:</u>
Nucleons are defined as the sub-atomic particles which are present in the nucleus of an atom. Nucleons are protons and neutrons.
The isotopic symbol of Helium-4 atom is 
Number of electrons = 2
Number of protons = 2
Number of neutrons = 4 - 2 = 2
We are given:
Mass of He-4 atom = 
Mass of 1 electron = 
Calculating the mass contributed by the nucleus = 
Mass of the nucleus of He-4 atom = 
To calculate the fraction of atom's mass contributed by the nucleus, we use the equation:

Putting values in above equation, we get:

Hence, the fraction of atom's mass contributed by nucleus is 0.99
1-Electric Energy
Example: A lightbulb is an example of electric energy
2-Sound Energy
Example: When a dog barks, that is sound energy
3-Solar Energy
Example: When we use the sun for energy. Like using it to dry our clothes.
4-Chemical Energy
Example: An example is a battery. That may not seem like it, but it is Chemical Energy.
5-Nuclear Energy
Example: A fission reaction at a nuclear powerplant
6-Thermal Energy
Example: A pot of water boiling on an Electric Stove
~Silver
Answer:
1 = one
2 = fluorine
3 = Bromine
4 = increase
5 = first increaseas and then decreases
hope it helps
Given :
Some compounds :
.
To Find :
Which of the following compounds has the most deshielded protons .
Solution :
Deshielded means nucleus whose chemical shift has been increased due to removal of electron density, magnetic induction, or other effects .
In simple words deshielding means the ability to shift protons .
Now , among Cl , I , Br and H . Cl is the most electron negative .
Therefore , deshielding will be more in
.
Hence , this is the required solution .