Principles of Chemistry - The Periodic Table

Question 1

how are elements in the periodic table arranged?

Answer 1

in order of increasing atomic number

Question 2

what are columns in the period table called?

Answer 2

groups - they indicate the number of electrons in the outer shell of an atom

Question 3

what are rows in the periodic table called?

Answer 3

periods - they indicate the number of shells in an atom

Question 4

how do you work out the electronic configuration of an electron?

Answer 4

• find the atomic number
• remember number of protons = number of electrons
• arrange the electrons in shells:
  1st shell can hold 2
  2nd shell can hold 8
  3rd shell can hold 8

Question 5

how do you classify elements as metals or non-metals?

Answer 5

metals:
- conduct electricity
- have oxides which are basic and react with acids to give a salt and water
non-metals:
- don’t conduct electricity (except graphite)
- have oxides which are acidic/neutral

Question 6

where are metals and non-metals on the periodic table?

Answer 6

metals are on the left and non-metals are on the right (and hydrogen)

Question 7

why do elements in the same group have similar properties?

Answer 7

they have the same number of electrons in their outer shell

Question 8

why are nobel gases inert?

Answer 8

they have a full outer shell of electrons