How did Mendeleev arrange the elements According to

How did Mendeleev arrange the elements? According to their mass

Why was Mendeleev’s periodic table useful? Led to the discovery of elements with predictable properties

True or False: On the periodic table, element properties repeat from row to row. true

What are the elements in the group 8 A called? Noble gases

Moving from left to right across a row of the periodic table, which increases by exactly one from element to element? Atomic number

On the periodic table, where are the metals? Left side or right side? Left side

What are metalloids? Elements that have some properties of metals and nonmetals

Which of the following elements is a nonmetal? Sodium, magnesium, aluminum, or sulfur. How do you know? Sulfur. Because it is the only element of those four that is on the nonmetal side of the periodic table

True or False: Metals are malleable. True

True or False: Metals are brittle. False

True or False: Metals are good conductors of electricity and heat. True

What is group 7 A called? Halogens

What two groups on the periodic table are most reactive? 1 A and 7 A

In Period 2, the metal lithium is reactive because it is in group 1 A. What other element in Period 2 is highly reactive? Fluorine. Because it is in group 7 A

How many valence electrons do the most highly reactive elements have? 1 or 7

As you move from left to right across a period, what happens to the number of valence electrons? It increases. Starts at 1, ends at 8

Which gases emit colors when an electric current is applied? ? Noble gases

Which of the following metals is the more reactive in group 1 A, sodium or potassium? Potassium

Across a period, elements go from being _______ to _________. Metals to nonmetals

The Lorax speaks for the _______ trees