Well we need to see the fossil
1 Hydrogen 1s1
2 Helium 1s2
3 Lithium 2s1
Answer:
the proton and the neutron
Explanation:
mass of The proton is approximately 1.6726 × 10^-27 Kg
mass of the electron is approximately 9.109 × 10^-31 Kg
mass of the neutron is approximately 1.6749 × 10^-27 Kg
Here we see that mass of proton and neutron is approximately similar.
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Lets see what is the mass of these particle IN atm unit
mass of these particles can also be described in form of amu(atomic mass unit)
1 atm is the mass defined as 1/12 th of mass of the carbon-12(c-12) atom.
In terms of unit atm
mass of proton = 1 amu
mass of electron = 5.45 × 10−4 amu
mass of neutron = 1 amu
hence we can say that mass of proton = mass of neutron.
mass of atom is sum of mass of all the neutron and proton in the atom.
Hence, mass of neturon and atom cannot be equal.
This makes option four the neutron and the atom , the wrong choice.
correct answer is the proton and the neutron
therefore, An atom contains one proton , one electron and one neutron then, mass of proton is similar in mass of neutron.
its volume this is the answer because the mercury will turn into gas. gas has more volume because it takes up more space as it spreads.
By convention, the symbol Z is assigned to the number of protons in the nucleus, or simply, the atomic number of an element. This is actually used when you want to determine the effective nuclear charge of a specific electron of an element. The equation is:
Z* = Z - S
where
Z* is the effective nuclear charge
Z is the atomic number
S is the number of electrons between the electron in question and the nucleus
There is due to a phenomenon called the shielding effect. This effect states that the farther the electron is from the nucleus, the lesser is its pull of force to the nucleus. That is the reason why the valence electrons (outermost electrons) are the ones always involved in chemicals reactions. Because they are not that strongly bonded to the nucleus of an atom.