the development of the periodic table

Question 1

state the stages of development of the periodic table

Answer 1

1.The elements were initially ordered according to their ATOMIC ‘WEIGHT’, even Though though grouped together due to having SIMILAR PROPERTIES.

2. DMITRI MENDELEEV realized what it made more sense to swap/ reverse the order of some elements. and left some spaces for undiscovered elements

Question 2

what order do electron shells fill up in

Answer 2

2,8,8,2

Question 3

what do metals/non metals want to always do

Answer 3

Metals always DONATE electrons an EMPTY OUTER SHELL form POSITIVE IONS (e.g. Na+). Again, transition metals are a bit more complicated, but they still form positive ions.

Non metals always accept electrons to gain a full outer shell They can form NEGATIVE IONS (e.g. 02-) or can share electrons to do this (more in bonding)

Question 4

what does a group number mean

Answer 4

number of electrons in the outer shell

Question 5

what are the group 1 metals

Answer 5

alkali metals (as they react with water to produce an alkali) they lose/donate their outer electron so their ions are all (1)+

Question 6

what happens are you go down the group

Answer 6

the outer electron is further from the nucleus so is donated more readily (the force of attraction is less)

Question 7

what type of element are group 7 and what happens to their ions and electrons halogens

Answer 7

they form (1)- ions as they accept 1 electron to gain a full outer sheel they fet less reactive down group (and boiling point increases)

Question 8

what groups are noble gases and what are there reactivity

Answer 8

group 0/8
very unattractive as they already have an empty outer shell

Question 9

what are transition metals

Answer 9

can donate different numbers of electrons