The correct option is D.
Mole is a measurement used in chemistry which allows us to measure out the same quantity of matter in different substances. Mole allows scientist to measure two substances, for instance, magnesium and sodium, which have equal amount of atoms. Thus, a mole of magnesium contains the same number of atoms as a mole of sodium.
Every combination of atoms is a molecule. A compound is a molecule made of atoms from different elements. All compounds are molecules, but not all molecules are compounds
The atomic number is the number at the top.
The atomic number is equal to the number of protons in an atom's nucleus. The atomic number determines which element an atom is. For example, any atom that contains exactly 47 protons in its nucleus is an atom of silver.
Answer:
i checked it again it's B
Explanation:
radiation sorry
The elements in each group have the same number of electrons in the outer orbital<span>. Those </span>outer<span> electrons are also called valence electrons. They are the electrons involved in chemical bonds with other elements. Every element in the first column (group one) has one electron in its </span>outer<span> shell.</span>