Which element contains the largest number of neutrons per atom?
a. bismuth-210 b. polonium-210c. astatine-210 d. astatine-211

a. Bismuth-210  have 127 neutrons

Explanation:

Atomic Structure:  

Atom is the smallest particle of an element.

it consists of Two portion i.e. orbitals and Nucleus

•orbitals have particles called electrons

•nucleus have neutrons and proton in it

overall particals are

So

Atomic Number:

The number of electrons or proton (number of electrons equal to the number of proton in an atom of element)

                               Atomic Number = Electron or Proton

Atomic Mass:

Atomic mass is the number of proton plus neutron in the nucleus.

                            Atomic Mass = Proton + neutron

Isotopes:

The atom having same atomic number and different atomic mass. This is because it have same number of protons and electrons but different number of neutrons.

So keeping in view the above details one can find out number of proton neutron or electron from its atomic mass and atomic number

A)

Number of neutron Bismuth-210:

This is an isotope of Bismith (Bi)

Atomic number of Bi = 83

Atomic Mass of Bi isotope = 210

Number of neutrons = Atomic Mass - Atomic number

Number of neutrons = 210 - 83

Number of neutrons in Bi= 127

B)

Number of neutron Polonium-210:

This is an isotope of Polonium

Atomic number of Po= 84

Atomic Mass of Po Isotop = 210

Number of neutrons = Atomic Mass - Atomic number

Number of neutrons = 210 - 84

Number of neutrons in Po= 126

C)

Number of neutron Astatine-210:

This is an isotope of At

Atomic number of At= 85

Atomic Mass of At Isotop = 210

Number of neutrons = Atomic Mass - Atomic number

Number of neutrons = 210 - 85

Number of neutrons in At= 125

D)

Number of neutron Astatine-211:

This is an isotope of At

Atomic number of At= 85

Atomic Mass of At Isotop = 211

Number of neutrons = Atomic Mass - Atomic number

Number of neutrons = 211 - 85

Number of neutrons in At= 126

So

Bismuth-210 have more neutrons than Polonium-210, Astatine-210, Astatine-211

answer carbon and three oxygen atoms;