Question

How do the atomic mass and atomic number compare for helium?

A Helium does not have an atomic number.
B The atomic mass is greater.
C The atomic mass and atomic number are equal.
D The atomic number is greater.

Answer 1

Answer:

Its nucleus also contains two neutrons. Since 2+2=4, we know that the mass number of the helium atom is 4. Finally, the helium atom also contains two electrons, since the number of electrons must equal the number of protons.

...

Mass Number.

Answer 2

Answer:

B) The atomic mass is greater than atomic number of Helium.

Explanation:

• Every element discovered has an atomic number depending on number of subatomic particles.
• Helium is an inert gas with atomic number 2.
• Helium is the second most abundant element in universe. On earth, it is less common.
• Atomic number being 2, the number of electrons in Helium atom is 2 which is equal to the number of protons.
• Atomic mass is the sum of number of protons and number of neutrons in the nucleus inside the atom and that is equal to 4.
• So, number of protons (2) and number of neutrons (2) in nucleus is summed up to give 4 units.