Question |
Answer |
What do elements present in group I of the periodic table have in common |
They all have one electron on their outer shell and they have similar chemical properties |
What are group I elements called |
Alkali metals |
Name some properties of the alkali metals |
Soft, shiny with low densitites |
Name the first three alkali metals in group I |
Lithium, Sodium and Potassium |
Alkali metals react with oxygen to form what |
Oxides |
If lithium is burned in the presence of oxygen, what is formed |
Lithium oxide |
If you cut sodium with a knife what happens |
It is initially shiny but then it reacts with the oxygen in the air and goes dull. All group 1 metals react this way |
Why is it necessary to store sodium and othre group 1 elements under oil |
Because it is so reactive |
Does reactivity increase or decrease as you go down the alkali metals in group 1 |
Increase |
Why is potassium more reactive than lithium |
Because potassium has more electrons, it has more shells and therefore the negatively charged electrons are further away from the positively charged protons. The forces holding them together are less and therefore they beak away easier |
What is formed when alkali metals react with water |
hydroxides and hydrogen gas |
Sodium reacts in water to form what |
Sodium hydroxide and hydrogen |
What is lithium used for |
Batteries |
Where would you use sodium |
Street lighting |
Where would you use potassium |
Fertilisers |