2.1: the periodic table

Question 1

who created an early form of the periodic table

Answer 1

Russian chemist

Dimitri Mendeleev

Question 2

how was it organised

Answer 2

• subatomic particles were unknown
• elements were placed in order of increasing mass of atoms.
• recognised chemical property of element varied periodically with increasing atomic mass
• arranged elements with similar properties vertically

Question 3

what is Mendeleev’s periodic law

Answer 3

properties of elements vary periodically with their atomic weight.

Question 4

5 key features of the modern periodic table

Answer 4

1) periodic table is arranged in order of increasing atomic number
2) horizontal rows are labelled periods 1-7
3) vertical columns are labelled groups 1-18
4) main group elements are elements in groups 1,2 and 13-18
5) the elements in groups 3-12 are known as transition metals

Question 5

what does the group of an element tell us?

Answer 5

• number of valence electrons
• in groups 13 -18 number of valence elcectrons = group number - 10
• valence electron determines chemical properties

Question 6

groups and their names

Answer 6

1 = alkali metals
2= alkaline earth metals
17 = halogens
18 = noble gases.

Question 7

what does the periods of the elements tell us?

Answer 7

• electronic configuration of an element
• ## period = occupied electron shells in element

Question 8

what are blocks

Answer 8

elements in blocks = same type of subshell

Question 9

s block

Answer 9

• group 1 & 2 and helium
• highest energy subshell configuration
  s(1) or s(2)

Question 10

p block

Answer 10

• groups 13 -18 except helium

s(2) p(1) to s(2) p(6)

Question 11

d block

Answer 11

groups 3-12

d(1) s(2) to d(10) s(2)

Question 12

f block

Answer 12

lanthanoids and actinoids

4f subshells progressively being filled = lanthanoids

5f subshells progressively being filled - antinoids