4.When trying to identify an unknown element, a scientist determines what other elements the unknown element reacts with chemically. Which property of the unknown element determines the other elements it reacts with?
A. The total number of neutrons in the unknown element
B. The total number of particles in the nucleus of the unknown element
C. The number of protons in the nucleus of the unknown element
D. The number of valence electrons in the unknown element
C. The number of protons in the nucleus of the unknown element
C. The number of protons in the nucleus of the unknown element determines the other elements it reacts with chemically. This is because the number of protons, also known as the atomic number, determines the identity of an element. Elements with different atomic numbers will have different chemical properties and will react differently with other elements.
The property of the unknown element that determines the other elements it reacts with chemically is the number of protons in the nucleus of the unknown element. This is referred to as the element's atomic number. The atomic number determines the element's position on the periodic table and is unique to each element.
To identify the unknown element, the scientist can compare its chemical reactivity with known elements. Elements in the same group or column on the periodic table tend to have similar chemical properties and react with the same elements in similar ways. This is because elements in the same group have the same number of valence electrons, which are the electrons in the outermost energy level of an atom.
Therefore, option C, the number of protons in the nucleus of the unknown element, is the property that determines the other elements it reacts with chemically.