To arrange the atoms from smallest to largest, you need to consider their atomic numbers, which represent the number of protons in the nucleus of an atom. The atomic number determines the position of an element in the periodic table and generally correlates with the size of the atom.
Here are the atoms listed from smallest to largest based on their atomic numbers:
- Be (Beryllium) - Atomic number: 4
- Na (Sodium) - Atomic number: 11
- Cs (Cesium) - Atomic number: 55
- Sr (Strontium) - Atomic number: 38
Therefore, the correct arrangement from smallest to largest is: Be, Na, Sr, Cs.