Answer:
D
Explanation:
In a Helium (He) atom, the atomic structure of the atom has 2 protons, 2 electrons and 2 neutrons. For an element X to be a Helium (He) atom, it must possess 2 protons. The number of neutrons present will determine its stability either if its probably radioactive or a natural occurring inert gas.
In option 1,
We have H-2. The symbol "H" is used to denote the element hydrogen in the periodic table and hydrogen has only 1 protons and 1 neutron making its mass number 2.
Option 2,
He -2 : here in this option, we have a helium atom, but with mass number of 2 only. Judging from the formula of mass number = protons + neutrons, we already have proton as 2, hence the number of neutrons there is zero (0)
Option 3,
He - 3 : just like in option 2, the only difference here is that the mass number is 3 hence making the number of neutrons just 1.
Option 4,
He - 4 : This option met the requirements of having 2 protons and 2 neutrons making a total of 4 which corresponds to the mass number.
Bromine has 35 protons, and in this case 46 neutrons, so 35 + 46 = 81
Therefore, the symbol is (subscript 35)(superscript 81) Br.
A mixture of oil and water is:
Heterogeneous
immiscible
<h3>What type of mixture of oil and water is?</h3>
The water molecules attract each other, and the oil molecules stick together. That causes oil and water to form two separate layers. Water molecules pack closer together, so they sink to the bottom, leaving oil sitting on top of the water. The mixture can be called as Emulsion. It is an immiscible liquid and the mixture is heterogeneous as oil floats on top of water surface but do not mix with it.
Thus, correct options are Heterogeneous and immiscible.
Find more information about Mixture here:
brainly.com/question/498370
I think it’s “Removed from”