Intro. to Periodic Table

Which of these is a metalloid?

• Na (#11)

• As (#33)

• O (#8)

Most metals share three common physical characteristics. Which of the options is not one of the three?

• shiny luster

• good conductor of electricity

• brittle

• Malleable

The periodic table is mostly made up of what type of element?

• Metals

• Nonmetals

• Metalloids

This class of elements are sometimes called "semiconductors."

• Metals

• Nonmetals

• Metalloids

Which of these is a property of metals?

• They're malleable

• They can't conduct electricity

• They are used in food

• They're very brittle

Which of these are usually brittle?

• Metal

• Nonmetal

Vertical (up and down) columns in the periodic table are called _________ of elements and have similar properties. 

• groups
• periods

The horizontal (left to right) rows on the periodic table are known as

• periods.
• atoms.
• groups or families.
• valence electrons.

What was Dmitri Mendeleev's greatest contribution to the history of the periodic table?

• He arranged all of the known elements by their atomic number
• He realised that there was a pattern of reactivity which repeated every 8 elements
• He predicted the existence (and properties) of new elements
• He identified the "law of triads" which became the groups

Why were there blank spaces left in Mendeleev's periodic table?                                              

• He didn't know what to put there.
•  Undiscovered elements not yet known.
• Multiple elements could have fit
• He forgot to add the elements in.