Question

Why is it impossible for an element to have an atomic number of 110.5?

a. atoms of an element have the same whole number of protons and neutrons

b. atoms of an element all have the same whole number of protons

c. exactly half of the isotopes would need an atomic number of 110 and half would need an atomic number of 111 which is very unlikely

d. atoms with atomic numbers greater than 100 are unstable

Answer 1

Answer: B

Explanation: The atomic number is based only on the number of protons in the nucleus of an atom. Since this is a count of whole numbers, it cannot be a decimal. It's either element 110 or 111, not 110.5.