Metric System, Atoms, and PT Test

Mendeleev created the first periodic table by arranging elements in order of ____.

• decreasing atomic mass

• increasing atomic mass

• increasing atomic number

• increasing melting points and densities

How did chemists change Mendeleev’s periodic table in the early 1900s?

• They included chemical properties such as bonding power.

• They included physical properties such as melting point and density.

• They used atomic mass instead of atomic number to organize the elements.

• They used atomic number instead of atomic mass to organize the elements.

Most metals are NOT ____.

• ductile

• good conductors of heat and electricity

• liquid at room temperature

• malleable

In the periodic table, the most reactive metals are found ____.

• in Group 1, the first column on the left

• in Period 1, the first row across the top

• in Groups 13 through 16 in the center

• in Periods 6 and 7 at the bottom

Which group contains the most elements?

• metalloids

• nonmetals

• metals

• transition elements

In an atom, the number of protons equals the number of ____.

• electrons

• neutrons

• atomic mass units

• isotopes

The elements in a column of the periodic table ____.

• have similar properties

• are in the same period

• have the same atomic mass

• have very similar chemical symbols

What information in the periodic table indicates the number of protons in an atom?

• the position of the element in its column

• the element’s chemical symbol

• the element’s atomic number

• the element’s atomic mass

The two most common alkaline earth metals are ____.

• copper and zinc

• iron and silver

• sodium and potassium

• calcium and magnesium

Which of the following statements about transition metals is true?

• They are never found uncombined in nature.

• They include familiar metals such as gold, silver, copper, and nickel.

• They are so soft that they can be cut with an ordinary knife.

• They are the most reactive of all the types of metals.