The noble gases are left out of the trends in atomic radii because there is great debate over the experimental values of their atomic radii.

The SI units for measuring atomic radii are the nanometer (nm) and the picometer (pm). 1 nm = 1 X 109 m; 1 pm = 1 X 10-12 m.

TLS Online TPP Program

#Id: 7742

#Section 2: General Biology

Atomic radii: The atomic radii of an atom depends on its position in the periodic table.

We can never determine the atomic radius of an atom because there is never a zero probability of finding an electron, and thus never a distinct boundary to the atom.

All that we can measure is the distance between two nuclei (internuclear distance).

TLS Online TPP Program

#Id: 7741

#Section 2: General Biology

Atomic radii: The atomic radii of an atom depends on its position in the periodic table.

We can never determine the atomic radius of an atom because there is never a zero probability of finding an electron, and thus never a distinct boundary to the atom.

All that we can measure is the distance between two nuclei (internuclear distance).

TLS Online TPP Program

#Id: 7739

#Section 2: General Biology

Atoms are characterised by:

Radius

Ionization energy

Electron affinity

Electronegativity

Metallic character

Oxidation potential

TLS Online TPP Program

#Id: 7738

#Section 2: General Biology

Which of the following are true for an element?

(i) Atomic number = number of protons + number of electrons

(ii) Mass number = number of protons + number of neutrons

(iii) Atomic number = number of protons = number of neutrons

(iv) Atomic number = number of protons = number of electrons

(a) (i) and (ii)

(b) (i) and (iii)

(c) (ii) and (iii)

(d) (ii) and (iv)

TLS Online TPP Program

#Id: 7737

#Section 2: General Biology

Calculate the number of electrons, protons and neutrons in 1 mole of 16^O^-2 ions.

TLS Online TPP Program

#Id: 7736

#Section 2: General Biology

The number of neutrons is equal to the difference between the mass number of the atom (M) and the atomic number (Z).