What is the concept of Absolute Zero

Absolute zero, technically known as zero kelvins, equals −273.15 degrees Celsius, or -459.67 Fahrenheit, and marks the spot on the thermometer where a system reaches its lowest possible energy, or thermal motion. There's a catch, though: absolute zero is impossible to reach.

Explanation:

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explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

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since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.