Compete the following table comparing atomic mass and mass number by enteng yes or no in each box.

atomic mass; mass number

1) NO ; YES

2) YES ; YES

3) YES ; YES

4) YES ; NO

5) NO; YES

Explanation:

An atomic mass is the mass of a single atom of a chemical element. It includes the masses of the 3 subatomic particles that make up an atom: protons, neutrons and electrons.

And also 1 atomic mass unit is defined as of the mass of a single carbon-12 atom.

Now, mass number of an element is the sum of protons and neutrons present in a single atom of that element.

Mass of the electrons is 9.10938356 × 10⁻³¹ kilograms

which is negligible.

And mass of proton and neutron is nearly but not exactly 1 u.

so, mass number is nearly but not exactly equal to atomic mass ,most of the times.

so,

1) only mass number can be used to calculate number neutrons present by simple subtracting atomic number(proton number) in mass number

2) both of these are found in periodic table

3) both can be found for individual atoms

4) mass number are different for isotopes but the atomic mass is calculated considering the isotopes(depends on availability of isotopes)

5)only mass number is given in isotopic symbol.