Periodic Table of Elements Questions

The modern periodic table has __ groups. (Write your answer as a number.)

This is how sodium appears in the periodic table. The arrow is pointing to sodium's

While looking at calcium (Ca) on the periodic table, a student needs to find an element with a greater atomic mass in the same period. Where should the student look?

While developing his periodic table, Dmitri Mendeleev broke his own rule and placed the element tellurium before iodine in the group. He did this even though tellurium's atomic mass was known to be greater than iodine's. In his notes, Mendeleev stated that he expected tellurium to have a lower atomic mass than iodine. However, all measurements continue to show that tellurium has a greater atomic mass than iodine even though tellurium acts like it has a lower atomic mass.What is the most likely reason that Mendeleev placed tellurium before iodine?

This is how osmium appears in the periodic table. Rounded to the nearest whole number, how many neutrons, on average, are in an atom of osmium?

Part of one row of the periodic table is shown.Which element's atoms have the greatest average number of neutrons?

This is how zirconium appears in the periodic table.Rounded to the nearest whole number, how many electrons are in an atom of zirconium?

What is the property that is most similar among all elements across one whole period called?

The elements in group 17 of the periodic table are all called halogens. All halogens have the same

In an element's square on the periodic table, the number with the greatest value represents the

This is how krypton appears in the periodic table. Rounded to the nearest whole number, how many protons are in an atom of krypton?

Elements in group 2 are all called alkaline earth metals. What is most similar about the alkaline earth metals?

Dmitri Mendeleev and Henry Moseley developed their periodic tables about forty years apart. During that time, many discoveries in chemistry were made.Which fact was most likely discovered between the time of Mendeleev's table and the time of Moseley's table that helped Moseley develop his version?

What is the lowest possible energy state of an atom called?

What are bundles of light emitted when an electron returns to a lower energy level?

The group of elements on the periodic table that have 7 valence electrons are also known as the

in ionic compounds, _______lose their valence electrons to form positively charged _____

The principal quantum numbers have the designation

Horizontal rows on the periodic table are called

Who is credited with the organization of the periodic table?