Unit 3 Flashcards
Who came up with the idea of a periodic table based off “octaves”?
Both Newlands and Mendeleev used this , the idea that every eighth element had similar properties
To which group do the noble gases belong?
group 0, they all have full outer shells
What do the grouos in the periodic table show?
The amount of electroms in their outer shell
If elements are in the same catagory they have similar what?
properties
Why are group 1 metals reactive?
Because they only have one electron to loose.
Explain why the group 1 metals get more reactive as you get lower down the group.
Because the distance from the nuleus to the outer shell is increased so it is easier for the negatively charged electon to escape the positive nucleus.Also because there is more shells between the the outer electron and the nucleus which reduces the effect of the nucleus.
Where are the transition metals positioned in the periodic table?
In the centre of the periodic table.
Why do the group 7 elements get less reactive as you go down the group?
Because the small the halogen the atom the more strongly the positive nucleus is felt because there are fewer shells of electronsto shield the positive charge, so electons are easily attracted.So atoms further down the group the greater the distance to the nucleus, so the positive attraction is less.
How can you tell the difference between permenent hard water and temporary hard water?
temporarily hard water will be softened by boiling.
What is hard water caused by?
The presence of calcium or magnesium
What does reaction hard water with soap form?
scum
What type of rection looses energy?
exothermic, this can be shown by a rise in temperature.
What type of reaction is it when energy is gained?
endothermic
What is a fuel which we have a strong possibility of using in the future?
hydrogen
How could you test for metal ions?
Through a flame test.
