7 valence electrons in an atom
Cold water<span> is </span>more dense<span> and will sink in room-temperature </span>water<span>. hope it helps :)</span>
Answer:
During dissolving, particles of solvent collide with particles of solute. They surround the particles of solute, gradually moving them away until the particles are evenly spread through the solvent.
Elements that have different atomic mass
Answer:
c) two different elements
Explanation:
A periodic table can be defined as the standard arrangement of chemical elements by atomic number, electronic configuration and chemical properties in a tabular form.
Generally, a proper representation of the mass number and atomic number of chemical elements is key and very important in chemistry.
Furthermore, as a rule, it should be noted that the mass number (nucleon number) is always larger than the atomic number(number of proton).
In the periodic table, all chemical elements are identified based on number of protons because it represents the atomic number.
This ultimately implies that, numbers of protons (atomic numbers) is used to differentiate an atom of one chemical element from the atom of another chemical element.
Hence, two atoms with different numbers of protons are two different elements.
For example, Hydrogen has one proton while Oxygen has 8 protons.
