Must contain: 6 protons, 6 electrons and 12 neutrons.
Compare the density of the object in question to the density of water. If its density is less than water, it will float. For example, oak floats because its density is 0.7 g/cm³. If the density of an object is greater than water, it will sink.
Answer:
The symbol of each element is, Ne, Na, Mg, and Al.
Explanation:
Below is the list of elements that has an atomic mass of less than 19.3 u.
The atomic mass of Neon is 20.1797 u and the atomic number is 10.
The atomic mass of Sodium is 22.989769 u and the atomic number is 11.
The atomic mass of Magnesium is 24.305 u and the atomic number is 12.
The atomic mass of Aluminium is 26.981539 u and the atomic number is 13.
Here, the symbol of each element is, Ne, Na, Mg, and Al.