A metalloid is a type of chemical element which has a preponderance of properties in between, or that are a mixture of, those of metals and nonmetals.
The number of neutrons in an atom is the number of particles present in its nucleus.
The atomic number is the number of protons whereas the mass number is the number of protons and number of neutrons together
This implies that the number of neutrons is the atom's mass number
The elements in the periodice table are not listed in alphabetical order, because the arragement in rows (periods) and columns (groups or familes), in increasing order of atomic number (number of protons of the atoms) permits to explain similarities among the elements, trend in some properties, and even predict properties of unknown elements.
For example, the elements of the first group (family), called alkaline metals, all have 1 valence electron, have similar physical properties (ductibility, malleability, luster, thermal and electricity conductivity), react in similar way with water, show a trend in the atomic radii and in the ionization energy.
You can tell similar stories for other groups like, alkalyne earth metals, halogens and noble gases.
You can also tell trends in electroneativities, and atomic radii, for a row of elements, as per the order they are in the row.
So, the current array resulted very helpul for chemists to explain and predict the behavior and properties of the elements.
The answer would be D. This is because sulfur is on it's own, meaning one. while tri is a prefix for three so there are three oxygen atoms.
UV exposure that leads to sunburn is proven in developing melanoma, the most dangerous of the three most common types of skin cancer.
