Isotopes of the same element differ only in the number of neutrons an atom has. Its still the same element because the number of protons define an element. Just their neutrons and mass number is different.
Answer:
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Atmospheric Pressure is the force per unit area exerted on a surface due to the weight of air molecules above it. It is caused by the collisions of the air molecules with that surface.:
I think it is "Known".
Radioactive decay is measured using a formula where the half-life <span>of an isotope is the time it takes for the original nuclei to decay half of its original amount.</span>
The atomic structure of an atom is well explained experimentally by different experiments like Rutherford's experiment etc
Based on these experiments it was determined that the atoms contains a central part known as nucleus which contains the positively charged sub atomic particles protons and neutral sub atomic particles neutron.
There is empty space around the nucleus in which negatively charged subatomic particles are found known as electrons.
So answers are
a) protons
b) neutrons
c) electrons
