The modern Periodic Table

Question 1

In the periodic table, what order is elements laid out in ?

Answer 1

There are around 100 elements which all materials are made of.

Increasing atomic number. Arranging elements like this mean that there are repeating patterns in properties of the elements.

Question 2

Why is the periodic table useful ?

Answer 2

easier to remember properties = organised
useful tool to work out which elements are metal and non metals. Metals to the left and non metals to the right

Question 3

What are groups ?

Answer 3

Elements with similar properties form columns

vertical columns are called groups

Question 4

What does the group number tell you ?

Answer 4

how many electrons in the outer shell

Question 5

exception to group number

Answer 5

group 0 = for example helium has two electrons in outer shell

Question 6

Why is knowing the group number useful ?

Answer 6

as the way atoms react depends upon the number of electrons in its outer shell, so elements in same group react in a similar way.

If you know properties of one element, you can predict properties of other elements in that group but also predictions about trend of reactivity

For example : groups 1s are metal so react in similar way and group 1 elements react more vigorously as you go down so group 7 reactivity decreased as you go down

Question 7

What are periods ?

Answer 7

the horizontal rows.
Each new period represents another full shell of electrons