Question

The picture shows a model of a helium atom and a model of a lithium atom.


Which of the following statements is true about the lithium and the helium atoms?
A.
There is no difference between helium and lithium.
B.
Lithium has more protons, neutrons, and electrons.
C.
Lithium is much smaller than helium.
D.
Helium has more protons, neutrons, and electrons.

Answer 1

B.

Lithium (atomic number 3) has 3 protons and, in a neutral atom, 3 electrons; helium (atomic number 2) has 2 protons and 2 electrons. The common lithium isotope (Li‑7) also has more neutrons (4) than the common helium isotope (He‑4, with 2 neutrons), so overall lithium has more protons, neutrons, and electrons.