The atomic radius is the distance between center of two bonded atoms.
Trend along period:
As we move from left to right across the periodic table the number of valance electrons in an atom increase.The atomic size tend to decrease in same period of periodic table because the electrons are added with in the same shell. When the electron are added, at the same time protons are also added in the nucleus. The positive charge is going to increase and this charge is greater in effect than the charge of electrons. This effect lead to the greater nuclear attraction. The electrons are pull towards the nucleus and valance shell get closer to the nucleus. As a result of this greater nuclear attraction atomic radius decreases.
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In group by addition of electron atomic radii increase from top to bottom due to increase in atomic number and addition of extra shell.
In this way Cl⁻ will have the largest atomic radii because one extra electron is added and its atomic number is already greater than fluorine.
In June 1998 in Japan a scientist discovered that neutrinos (which is a type of particle) has weight, mass. This was later proven with some very convincing strong evidence.
The rate of evaporation is equal to rate of condensation in equilibrium......It means the evaporation rate becomes constant.....And thus equilibrium attained !!!
