Mass number is the number of protons and neutrons in an atom, and it tells us about the mass of the atom in amu, or atomic mass units. Atomic mass is the average mass of all the isotopes of a certain type. It is a weighted average that takes into account the abundances of all of the different isotopes
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Any element in group 18 has eight valence electrons (except for helium, which has a total of just two electrons). Examples include neon (Ne), argon (Ar), and krypton (Kr). Oxygen, like all the other elements in group 16, has six valence electrons.
The process through which Polonium is most likely to become stable is: B. alpha decay.
An unstable element refers to a chemical element that lose particles because its nucleus contain an excess of internal energy (neutron or proton).
This ultimately implies that, an unstable element is radioactive in nature.
In Science, some examples of an unstable element are:
Polonium is a chemical element with a large, unstable nucleus.
Basically, the most stable isotope of Polonium is Polonium-209, which typically undergoes an alpha decay to form lead-205 and the emission of an alpha particle.
⇒ 
----> 
In conclusion, we can deduce from the above chemical equation that Polonium is most likely to become stable through an alpha decay.
Read more: brainly.com/question/18214726
At STP (standard temperature and pressure conditions), 1 mol of any gas occupies 22.4 L
This rule is applied to O₂
22.4 L volume occupied by 1 mol
Therefore 83.4 L occupied by - 1/ 22.4 x 83.4 = 3.72 mol
stoichiometry of O₂ to H₂O is 1:2
then the number of moles of water produced - 3.72 mol x 2= 7.44 mol
mass of water produced - 7.44 mol x 18.01 g/mol = 134.1 g
correct answer is D
1.) Gas given off
2.) precipitate formed
3.) large amount of heat given off
4.) Color change
