Periodic Table and Trends

Where are metals located on the periodic table?

On the left side.

What are the physical properties of metals?

Good conductors, malleable, ductile, high tensile strength, and lustrous.

Which is the only metal that is liquid at room temperature?

Mercury (Hg).

What are the characteristics of Group 1 alkali metals?

One valence electron; react violently with water.

What are the characteristics of Group 2 alkaline earth metals?

Two valence electrons; harder and less reactive than alkali metals.

Which groups comprise the transition metals?

Groups 3 through 12 (d-block elements).

What are the two series of inner transition metals?

Lanthanides and actinides.

Where are metalloids located and what is a key property?

Between metals and nonmetals; they act as semiconductors.

Where are nonmetals located on the periodic table?

On the right side.

What are the characteristics of Group 17 halogens?

Seven valence electrons; highly reactive nonmetals.

What are the characteristics of Group 18 noble gases?

Eight valence electrons; highly stable and unreactive.

What two main factors determine all periodic trends?

Nuclear charge and electron shielding.

How does atomic radius change across a period?

It decreases from left to right.

How does atomic radius change down a group?

It increases from top to bottom.

What is ionization energy?

The energy required to remove an electron from an atom.

How does ionization energy change across a period?

It increases from left to right.

How does ionization energy change down a group?

It decreases from top to bottom.

How does the radius of a cation compare to its neutral atom?

It is smaller because electrons are removed.

How does the radius of an anion compare to its neutral atom?

It is larger because electrons are added.

What is electronegativity?

An atom's ability to attract electrons from another atom.

Who proposed the law of triads in the early 1800s?

J. W. Dobereiner

What was John Newlands' 'Law of Octaves'?

The idea that properties are similar every 8 elements when listed from lightest to heaviest.

What distinguished Mendeleev's periodic table from earlier versions?

It contained blank spaces for undiscovered elements and was organized by atomic mass and properties.

Who developed the Modern Periodic Law by arranging elements by atomic number in 1913?

Moseley

What are the horizontal rows and vertical columns on the periodic table called?

Rows are periods, and columns are groups or families.