chem ch 6

periodic law

the law that states that when elements are arranged in order of their atomic number, we observe a periodic repetition of their physical and chemical properties.

18

how many groups are on the periodic table?

vertical

Are groups horizontal or vertical?

7

How many periods are there?

ductile, good conductors of heat and electricity, lustrous, malleable, and solid

Name all of the physical properties of elements in alphabetical order

oxidized

Metals might not appear lustrous at first, because they often are ----- by exposure to air.

18

how many non metals are there?

allotropes

different forms of the same element

metalloids

elements that have properties of both metals and nonmetals.

alkali metals

What are group 1 elements called?

1

how many valence electrons does group 1 have

alkaline earth metals

What are group 2 elements called?

Halogens

what group 17 elements called

reactive

The halogens are very ------ , due to being one electron short of a full outer shell.

noble gases

what group 18 elements called

24

how many synthetic elements are there?

representative elements

the A groups on the periodic table that have a wide range of properties