The atomic radius of hydrogen atom is:
A. 25pm
B. 30pm
C. 53pm
D. 43pm

Hint: Atomic radius is measured as the distance between the centre of the nucleus to the boundary of the electrons surrounded by it. Atoms are the smallest quantity of the universe. It is not possible to define its boundary to so much or precision. Now let us see the complete step by step solution to know the value of the atomic radius of the hydrogen atom.

Complete step by step solution:
Generally the atomic radius is measured as the distance between the centre of the nucleus to the boundary of the electrons surrounded by it. For any two covalently bonded atoms it is calculated by dividing the distance between the nuclei of the atom by two. We know that hydrogen atom has an atomic number as 1 and its atomic weight is 1.008u. The atomic radius of the hydrogen atom is measured as 53pm.

Hence, option C is correct.

Additional Information:
-Atomic radii follow some trends in periodic table such as: it generally decreases along each period from the alkali metal to Noble gas.
-It increases down the group.
Generally the trend has seen that the atomic radius increases sharply between the Noble gas -at the end of each period and the alkali metal at the starting of the next period.

Note: As we know that electrons don't have any defined orbits or sharply defined ranges. So, due to this atomic radius is measured as Van Der Waals radius, ionic radius and covalent radius. Van Der Waals radius is greater than covalent radius which is greater than ionic radius.